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Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals with Type 1 or Type 2 Diabetes

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Title: Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals with Type 1 or Type 2 Diabetes
Language: English
Authors: Plotnikoff, Ronald C., Lippke, Sonia, Reinbold-Matthews, Melissa, Courneya, Kerry S., Karunamuni, Nandini, Sigal, Ronald J., Birkett, Nicholas
Source: Measurement in Physical Education and Exercise Science. Apr 2007 11(2):73-91.
Availability: Routledge. Available from: Taylor & Francis, Ltd. 325 Chestnut Street Suite 800, Philadelphia, PA 19106. Tel: 800-354-1420; Fax: 215-625-2940; Web site: http://www.tandf.co.uk/journals
Peer Reviewed: Y
Page Count: 19
Publication Date: 2007
Document Type: Journal Articles
Reports - Evaluative
Descriptors: Physical Activities, Physical Activity Level, Diabetes, Validity, Intention, Foreign Countries, Measures (Individuals), Guidelines, Health Behavior, Age Differences, Behavior Patterns
Geographic Terms: Canada
DOI: 10.1080/10913670701294062
ISSN: 1091-367X
Abstract: This study was designed to test the validity of a transtheoretical model's physical activity (PA) stage measure with intention and different intensities of behavior in a large population-based sample of adults living with diabetes (Type 1 diabetes, n = 697; Type 2 diabetes, n = 1,614) and examine different age groups. The overall "specificity" (classified correctly as inactive) for Type 1 diabetes was 69.3% based on the percentage of individuals in precontemplation, contemplation, and preparation not meeting Canada's PA guidelines. "Sensitivity" (classified correctly as active) was 82.5% based on the proportion of active participants in action and maintenance. In the Type 2 diabetes group, the overall specificity and sensitivity was 63.9% and 88.2%, respectively. No significant differences were found between the diabetes groups for stage distribution patterns, and sensitivity and specificity values. The majority of the study hypotheses related to intention and behaviors were confirmed, providing further supportive evidence for the utility of this PA staging measure for the diabetes population. (Contains 2 figures, 4 tables and 2 footnotes.)
Abstractor: As Provided
Number of References: 40
Entry Date: 2009
Accession Number: EJ825850
Database: ERIC
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  Value: <anid>AN0024951643;7mm01jun.07;2019Mar06.12:19;v2.2.500</anid> <title id="AN0024951643-1">Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals With Type 1 or Type 2 Diabetes. </title> <p>This study was designed to test the validity of a transtheoretical model's physical activity (PA) stage measure with intention and different intensities of behavior in a large population-based sample of adults living with diabetes (Type 1 diabetes, n = 697; Type 2 diabetes, n = 1,614) and examine different age groups. The overall specificity (classified correctly as inactive) for Type 1 diabetes was 69.3% based on the percentage of individuals in precontemplation, contemplation, and preparation not meeting Canada's PA guidelines. Sensitivity (classified correctly as active) was 82.5% based on the proportion of active participants in action and maintenance. In the Type 2 diabetes group, the overall specificity and sensitivity was 63.9% and 88.2%, respectively. No significant differences were found between the diabetes groups for stage distribution patterns, and sensitivity and specificity values. The majority of the study hypotheses related to intention and behaviors were confirmed, providing further supportive evidence for the utility of this PA staging measure for the diabetes population.</p> <p>Keywords: stages of change; transtheoretical model; physical activity; diabetes mellitus; validation; sensitivity; specificity</p> <p>Researchers have documented that physical activity (PA) improves outcomes for individuals with Type 1 and Type 2 diabetes ([<reflink idref="bib6" id="ref1">6</reflink>]; [<reflink idref="bib16" id="ref2">16</reflink>]; [<reflink idref="bib36" id="ref3">36</reflink>]), and yet, participation in PA remains inadequate in this population. Canadian data indicate over 60% of individuals with diabetes ages 35 to 64 years and 76% ages 65 years and older are insufficiently active to experience health benefits ([<reflink idref="bib25" id="ref4">25</reflink>]).</p> <p>Social–cognitive theories that attempt to understand, predict, and change volitional behavior could potentially assist researchers and practitioners in addressing this important health issue. The transtheoretical model (TTM), also known as the "stages of change" model ([<reflink idref="bib32" id="ref5">32</reflink>]), is an integrative model of intentional behavior change that provides a framework for directing the design, content, implementation, and evaluation of interventions ([<reflink idref="bib23" id="ref6">23</reflink>]). TTM conceives behavioral change as a process involving progress through a series of five stages: (a) <emph>precontemplation,</emph> not considering behavior change in the next 6 months; (b) <emph>contemplation,</emph> considering behavior change within the next 6 months; (c) <emph>preparation,</emph> preparing for behavior change within the next 1 month; (d) <emph>action,</emph> overt behavior change has been made within the last 6 months; and (e) <emph>maintenance,</emph> maintaining the desired behavior change. The TTM has been used in behavior-change interventions with a broad range of health-related behaviors ([<reflink idref="bib5" id="ref7">5</reflink>]).</p> <p>The TTM model has been criticized for its use without adequate validation (Adams & White, 2004; Brug et al., 2005 [<reflink idref="bib2" id="ref8">2</reflink>]; [<reflink idref="bib23" id="ref9">23</reflink>]). For instance, incorrect applications of the staging algorithm and a paucity of validated staging algorithms (i.e., no gold standard) may have, in some studies, resulted in the classification of individuals into inappropriate stages of change ([<reflink idref="bib1" id="ref10">1</reflink>]; [<reflink idref="bib33" id="ref11">33</reflink>]).</p> <p>The five stages of TTM discussed previously have not only been proposed to reflect differences in individuals' actual behavior, but differences in the intention to change behavior ([<reflink idref="bib23" id="ref12">23</reflink>]). In terms of behavior, individuals in precontemplation, contemplation, and preparation should not significantly differ in behavior; nor should those in action and maintenance. The greatest significant behavior differences between the stages are expected to appear between preparation and action. The intention to adopt a behavior is thought to increase from precontemplation to contemplation, and from contemplation to preparation; and the intention to adopt the behavior becomes irrelevant as soon as the behavior is reached (i.e., action stage; [<reflink idref="bib23" id="ref13">23</reflink>]). This hypothesis was supported in one study ([<reflink idref="bib9" id="ref14">9</reflink>]), but it was not replicated in another ([<reflink idref="bib3" id="ref15">3</reflink>]).</p> <p>Concurrent validity for TTM has generally been supported by findings that individuals in earlier stages of change participate in less PA than those closer to the action stage of change ([<reflink idref="bib3" id="ref16">3</reflink>]; [<reflink idref="bib11" id="ref17">11</reflink>]; [<reflink idref="bib19" id="ref18">19</reflink>]; [<reflink idref="bib34" id="ref19">34</reflink>]; [<reflink idref="bib35" id="ref20">35</reflink>]). Also, a stage measure is associated with both self-reported PA behavior and measures of fitness levels ([<reflink idref="bib35" id="ref21">35</reflink>]). This validation of stages for PA has been conducted across age groups (for a review, see [<reflink idref="bib23" id="ref22">23</reflink>]), overweight populations ([<reflink idref="bib34" id="ref23">34</reflink>]), stroke patients ([<reflink idref="bib14" id="ref24">14</reflink>]), and worksite populations ([<reflink idref="bib22" id="ref25">22</reflink>]).</p> <p>A stage measure must have a high specificity and sensitivity to evaluate with construct validity ([<reflink idref="bib19" id="ref26">19</reflink>]). The specificity and sensitivity of a stage measure provides information relating to whether actual active individuals (who are measured using behavioral criteria; e.g., published guidelines) are correctly classified as active (and vice versa) using a stage measure. The first three stage groups of TTM (precontemplation, contemplation, and preparation) can be labeled as <emph>inactive,</emph> and the two latter stages (action and maintenance) can be labeled as <emph>active</emph>. A clear threshold is needed to calculate a specificity and sensitivity such as meeting Canadian Public Health Guidelines of achieving at least 120 min of moderate intensity PA per week. If a stage measure was ideal in differentiating active and inactive individuals using this threshold, 0% of individuals in precontemplation, contemplation, and preparation—in contrast to 100% of individuals in action and maintenance stages—should be achieving Canadian Public Health Guidelines.</p> <p>Different intensities of PA (i.e., vigorous, moderate, and mild) have been examined across the stages of TTM. [<reflink idref="bib23" id="ref27">23</reflink>] found no adjacent stage differences for mild PA and that mild intensity PA was associated with poor specificity and sensitivity—leading to the conclusion that stages of change are useful only with respect to moderate and strenuous intensity activity. A possible explanation for Nigg's observation could be the moderating effects of age and the differing criteria used in assessing the stage and behavior test variable. [<reflink idref="bib35" id="ref28">35</reflink>] found that in older adults (but not for any other age group), mild activity significantly differentiated between action and maintenance stages. As pointed out in Nigg's review, researchers need to consider both PA intensity and age in the validation of a stage measure.</p> <p>Based on the previous discussion, this study was designed to examine the validity of a TTM stage measure for PA. The study objectives were to (a) determine specificity and sensitivity of a PA stage measure using Canadian Public Health Guidelines of achieving at least 120 min of moderate intensity PA per week as a threshold, (b) examine PA behavior and intention patterns of different PA intensities across the TTM stages, and (c) examine the previous research objectives by age groups. A subsidiary objective was to simultaneously determine the explained variances of stage, age, and diabetes type in differentiating the stage groups for various PA intensities and PA intention. Given the etiological ([<reflink idref="bib36" id="ref29">36</reflink>]) and potential behavioral differences of these diseases, study objectives a and b were examined for the two diabetes groups separately. No researchers have explored the validity of the TTM's stage measure in populations of Type 1 or Type 2 diabetes patients.</p> <hd id="AN0024951643-2">METHOD</hd> <p></p> <hd id="AN0024951643-3">Participants</hd> <p>Study participants were recruited using two recruitment protocols as part of a population-based longitudinal assessment of PA determinants (Alberta Longitudinal Exercise and Diabetes Research Advancement [ALEXANDRA] study; [<reflink idref="bib25" id="ref30">25</reflink>]; Plotnikoff et al., in press). The study received approval from a University Ethics Review Board. The first recruitment method involved soliciting study participation from Alberta residents listed in the Canadian Diabetes Association registry. Postage-paid return questionnaires (<emph>N</emph> = 4,609) and consent forms were mailed with the association's newsletter to all Alberta members, requesting completion by only those members diagnosed with diabetes (as an undisclosed number of members of this association do not have diabetes). A follow-up postcard reminder was sent 12 days after the initial mailing. A total of 1,923 individuals (Type 1 diabetes = 609; Type 2 diabetes = 1,314) submitted completed surveys.</p> <p>The second recruitment strategy used a randomized-digit dialing telephone protocol, and it obtained a random sample of 396 individuals with diabetes (Type 1 diabetes = 88, Type 2 diabetes = 308) living in the province of Alberta (i.e., all residential houses with registered telephone numbers were eligible). Households were contacted to recruit individuals with diabetes who were (a) residing in the contacted household or (b) not residing in the contacted household but identified as possible participants by family members or friends. Once contact by telephone was established with the diabetic individual, a postage-paid return questionnaire and consent form were mailed.</p> <p>There were no study exclusion criteria for the Type 1 and Type 2 diabetes groups. The two recruited samples demonstrate compatible demographic, health, and behavioral characteristics examined in this study (Plotnikoff et al., in press); consequently, participants recruited through each procedure were pooled for subsequent analyses to increase the sample size.</p> <p>At Time 1 of the ALEXANDRA study, 2,319 individuals diagnosed with diabetes (Type 1 or Type 2) returned completed instruments (details of study response rates are reported elsewhere; [<reflink idref="bib25" id="ref31">25</reflink>]; Plotnikoff et al., in press). Seven individuals were excluded from the study, as they did not specify diabetes type. Analyses for this study were conducted on 697 individuals with Type 1 diabetes and 1,615 individuals with Type 2 diabetes who completed the baseline assessment of the ALEXANDRA study (see Table 1).</p> <p>TABLE 1. Demographic and Health Characteristics of Participants</p> <p> <ephtml> <table><thead valign="bottom"><tr><td /><td>Type 1</td><td>Type 2</td><td>Test of Significance for Comparison Between Type 1 and Type 2</td></tr><tr><td>Variable</td><td>n</td><td>%</td><td>M</td><td>SD</td><td>n</td><td>%</td><td>M</td><td>SD</td></tr></thead><tbody><tr><td><italic>Demographic factors</italic></td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td> Age</td><td>—</td><td /><td char=".">51.1</td><td char=".">17.1</td><td>—</td><td>—</td><td char=".">62.9</td><td char=".">12.1</td><td char=".">−19.0, 2309</td></tr><tr><td> Gender</td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>  Woman</td><td char=".">374</td><td char=".">53.5</td><td>—</td><td>—</td><td char=".">784</td><td char=".">49</td><td>—</td><td>—</td><td /></tr><tr><td>  Man</td><td char=".">323</td><td char=".">46.5</td><td>—</td><td>—</td><td char=".">830</td><td char=".">51</td><td>—</td><td>—</td><td char="."><bold>4.7</bold></td></tr><tr><td> Marital–partner status</td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>  Currently single</td><td char=".">194</td><td char=".">28</td><td>—</td><td>—</td><td char=".">379</td><td char=".">24</td><td>—</td><td>—</td><td /></tr><tr><td>  Currently partnered</td><td char=".">503</td><td char=".">72</td><td>—</td><td>—</td><td char=".">1,235</td><td char=".">77</td><td>—</td><td>—</td><td char="."><bold>4.6</bold></td></tr><tr><td> Education</td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>  No university completed</td><td char=".">394</td><td char=".">57</td><td>—</td><td>—</td><td char=".">1,065</td><td char=".">66</td><td>—</td><td>—</td><td /></tr><tr><td>  University degree or degrees</td><td char=".">303</td><td char=".">44</td><td>—</td><td>—</td><td char=".">549</td><td char=".">34</td><td>—</td><td>—</td><td char="."><bold>18.3</bold></td></tr><tr><td> Gross family income</td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>  <60,000</td><td char=".">401</td><td char=".">58</td><td>—</td><td>—</td><td char=".">1,146</td><td char=".">71</td><td>—</td><td>—</td><td /></tr><tr><td>  ≥60,000</td><td char=".">296</td><td char=".">42</td><td>—</td><td>—</td><td char=".">468</td><td char=".">29</td><td>—</td><td>—</td><td char="."><bold>39.9</bold></td></tr><tr><td><italic>Health factors</italic></td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td> Body Mass Index</td><td>—</td><td>—</td><td char=".">26.3</td><td char=".">4.5</td><td>—</td><td>—</td><td char=".">29.8</td><td char=".">6.3</td><td char=".">–13.0, 2253</td></tr><tr><td> Smoking status</td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>  Currently smoking</td><td char=".">58</td><td char=".">8</td><td>—</td><td>—</td><td char=".">129</td><td char=".">8</td><td>—</td><td>—</td><td char="."><bold>0.2</bold></td></tr><tr><td> Insulin</td><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>  Takes insulin</td><td char=".">697</td><td char=".">100</td><td>—</td><td>—</td><td char=".">339</td><td char=".">21</td><td>—</td><td>—</td><td char="."><bold>1172.5</bold></td></tr><tr><td> Use of oral hypoglycaemic medication</td><td char=".">74</td><td char=".">11</td><td>—</td><td>—</td><td char=".">1,081</td><td char=".">67</td><td>—</td><td>—</td><td char="."><bold>617.5</bold></td></tr><tr><td> Heart disease</td><td char=".">127</td><td char=".">18</td><td>—</td><td>—</td><td char=".">371</td><td char=".">23</td><td>—</td><td>—</td><td char="."><bold>6.3</bold></td></tr><tr><td> High cholesterol</td><td char=".">256</td><td char=".">37</td><td>—</td><td>—</td><td char=".">952</td><td char=".">59</td><td>—</td><td>—</td><td char="."><bold>93.1</bold></td></tr><tr><td> Hypertension</td><td char=".">326</td><td char=".">47</td><td>—</td><td>—</td><td char=".">1,017</td><td char=".">63</td><td>—</td><td>—</td><td char="."><bold>54.2</bold></td></tr><tr><td><sup>a</sup><italic>n</italic> = 697. <sup>b</sup><italic>n</italic> = 1,615. <sup>c</sup> Results of the chi-square analysis, <italic>df</italic> = 1. <sup>d</sup> ± tests with reported degrees of freedom.</td></tr><tr><td>All chi-square results are continuity adjusted, <sup>*</sup><italic>p</italic> < .05. <sup>**</sup><italic>p</italic> < .001.</td></tr></tbody></table> </ephtml> </p> <p>Sample characteristics for the Type 1 diabetes group were as follows: mean age = 51.1 years (<emph>SD</emph> = 17.1); 46.5% men and 53.5% women; mean BMI (Body Mass Index) = 26.3 (<emph>SD</emph> = 4.4), with 56.8% classified as overweight or obese. The characteristics for the Type 2 diabetes group were as follows: mean age = 62.9 years (<emph>SD</emph> = 12.1); 51.4% men and 48.6% women; mean BMI = 29.6 (<emph>SD</emph> = 5.9), with 79.1% classified as overweight or obese. The demographic characteristics of our study generally reflect Canada's diabetic population in terms of age and sex distributions ([<reflink idref="bib16" id="ref32">16</reflink>]).</p> <hd id="AN0024951643-4">Measures</hd> <p></p> <hd id="AN0024951643-5">Demographic factors</hd> <p>Questions based on the Statistics Canada (2001) [<reflink idref="bib3" id="ref33">3</reflink>] census were used to assess demographic characteristics, which include age, gender, ethnic origin, marital status, educational level, gross annual family income, and employment status. In addition, the following self-reported health factors were assessed ([<reflink idref="bib26" id="ref34">26</reflink>]; [<reflink idref="bib27" id="ref35">27</reflink>]): diabetes type, height and weight to calculate BMI, level of perceived disability influencing PA participation rated on a 6-point scale ranging from 0 (<emph>no limitation</emph>) to 5 (<emph>complete limitation</emph>), daily use of insulin or oral antihyperglycemic medication, smoking behavior, elevated blood pressure, and elevated cholesterol levels.</p> <hd id="AN0024951643-6">Godin Leisure-Time Exercise Questionnaire (GLTEQ; Godin & Shephard, 1985)</hd> <p>PA was measured using a modified version ([<reflink idref="bib7" id="ref36">7</reflink>]) of the GLTEQ ([<reflink idref="bib15" id="ref37">15</reflink>]). This self-report measure, which has been extensively validated with physiological and anthropometric markers (i.e., VO<subs>2</subs> max and body fat; [<reflink idref="bib15" id="ref38">15</reflink>]; [<reflink idref="bib17" id="ref39">17</reflink>]), served as the study's standard of PA level ([<reflink idref="bib15" id="ref40">15</reflink>]). Participants were asked to report the mean number of sessions per week and mean duration per week of vigorous (heart beats rapidly, sweating), moderate (not exhausting, light perspiration), and mild (minimal effort, no perspiration) PA in the past 1 month. Only activities lasting 10 min or longer were considered in the calculation of participant responses ([<reflink idref="bib7" id="ref41">7</reflink>]). Responses (product of frequency and duration) for each of these three activity categories were then converted to MET (metabolic equivalent) minutes by multiplying the weekly minutes of mild activity by 2.5 METs ([<reflink idref="bib2" id="ref42">2</reflink>]), moderate activity by 4.0 METs ([<reflink idref="bib4" id="ref43">4</reflink>]), and vigorous activity by 7.5 METs ([<reflink idref="bib4" id="ref44">4</reflink>]). Individuals who accumulated at least 480 weekly moderate or vigorous MET minutes (which is equivalent to 120 min of moderate activity per week),[<reflink idref="bib4" id="ref45">4</reflink>] or both, were classified as meeting Canadian Public Health Guidelines ([<reflink idref="bib16" id="ref46">16</reflink>]). As an example, this could be achieved by 30 min of brisk walking four times per week.</p> <hd id="AN0024951643-7">Stages of change</hd> <p>To assess current stage of PA motivational readiness, a staging question was employed ([<reflink idref="bib30" id="ref47">30</reflink>]) based on the work of [<reflink idref="bib20" id="ref48">20</reflink>] and [<reflink idref="bib21" id="ref49">21</reflink>]. The stages of change categories were (a) <emph>precontemplation,</emph> "I presently do not get regular physical activity and do not plan to do so in the next 6 months"; (b) <emph>contemplation,</emph> "I presently do not get regular physical activity, but I have been thinking about doing so within the next 6 months"; (c) <emph>preparation,</emph> "I presently do not get regular physical activity, but I plan to in the next 30 days"; (d) <emph>action,</emph> "I presently get regular physical activity, but I have only begun doing so within the past 6 months"; and (e) <emph>maintenance,</emph>"I presently get regular physical activity and have been doing so for longer than 6 months." In this study, regular PA was defined as "doing activities such as brisk walking, recreation, and sporting activities (e.g., jogging, swimming, bicycling, skiing) all at a moderate intensity of a brisk walking pace (or faster). These free-time activities did not include household chores or physical labor on the job. For moderate activity to be regular, activity must yield a total of 30 min or more per day and be done at least 4 days per week."</p> <hd id="AN0024951643-8">Behavioral intention</hd> <p>Behavioral intention was assessed using an 11-point scale with 10% intervals (0% =1  to 100% =1l ). The participants were asked, "On a scale of 0% to 100% how likely is it that you will get regular physical activity within the next 6 months?" ([<reflink idref="bib10" id="ref50">10</reflink>]; see [<reflink idref="bib28" id="ref51">28</reflink>], [<reflink idref="bib29" id="ref52">29</reflink>], for psychometric information on this measure).</p> <p>For the previous measures, "regular" PA is defined as accumulating at least 30 min of moderate intensity (or greater) PA per day at least 4 days per week ([<reflink idref="bib16" id="ref53">16</reflink>]). Moderate activity is defined as equivalent to the pace of a brisk walk. Activity could be in one long session (e.g., 30 min at a time) or in multiple shorter sessions, provided each was at least 10 min in duration.</p> <hd id="AN0024951643-9">Procedures and Analyses</hd> <p>All analyses were carried out using SPSS version 13. Data were initially screened for discrepant responses, missing data, and multicollinearity problems in accordance with previous recommendations ([<reflink idref="bib37" id="ref54">37</reflink>]). Descriptive statistics were examined for all study variables.</p> <p>Sensitivity–specificity analysis was carried out to determine the effectiveness of the staging instrument for classifying individuals with Type 1 and Type 2 diabetes based on their PA behavior. For the sensitivity–specificity analysis, individuals were classified as correctly inactive (according to the GLTEQ) if they were in the precontemplation, contemplation, or preparation stage. Accordingly, individuals in the action or maintenance stage were classified as correctly active (according to the GLTEQ). Sensitivity is the property of a test to detect individuals correctly classified as meeting the reference criteria (in particular, sensitivity is the proportion of individuals who were active according to the stage classification among all individuals meeting public health guidelines). Specificity is the property of a test to detect individuals correctly classified as not meeting the reference criteria (in particular, specificity is the proportion of individuals who were inactive according to the stage classification among all individuals not meeting public health guidelines; [<reflink idref="bib13" id="ref55">13</reflink>]; [<reflink idref="bib19" id="ref56">19</reflink>]). Chi-square analyses were used to determine if different patterns between the two diabetes types existed in the specificity–sensitivity results (Research Objectives a and c).</p> <p>The hypothesized stage differences were tested using analyses of variances with planned contrasts (Research Objectives b and c). To test our subsidiary research objective, PA behavior and intention served as the dependent variables, with diabetes type, stage, and age as factors. Two separate multivariate analyses of variance (MANOVAs) were conducted with the dependent variables: (a) vigorous, moderate, and mild PA and (b) intention and combined vigorous–moderate PA.</p> <hd id="AN0024951643-10">RESULTS</hd> <p>Of the 2,312 participants, 2,278 answered the staging items. Five individuals in the Type 1 group (0.7%) and 28 individuals of the diabetes Type 2 group (1.4%) did not respond to the staging items and were consequently excluded from the analysis (see Table 2).</p> <p>TABLE 2. Stage Measure Sensitivity and Specificity in Terms of the Canadian Public Health Guidelines for Physical Activity (120 min per Week) Differentiated by Diabetes Type</p> <p> <ephtml> <table><thead valign="bottom"><tr><td /><td>Type 1 Diabetes Classification (n)</td><td>Type 2 Diabetes Classification (n)</td></tr><tr><td>Stage</td><td>Inactive</td><td>Active</td><td>Inactive</td><td>Active</td></tr></thead><tbody><tr><td>Inactive according to stage (PC, C, and P)</td><td><bold>277</bold> (PC = 77, C = 90, P = 110)</td><td><bold>51</bold> (PC = 4, C = 15, P = 32)</td><td><bold>652</bold> (PC = 168, C = 226, P = 258)</td><td><bold>67</bold> (PC = 13, C = 19, P = 35)</td></tr><tr><td>Active according to stage (A and M)</td><td><bold>123</bold> (A = 30, M = 93)</td><td><bold>241</bold> (A = 39, M = 202)</td><td><bold>368</bold> (A = 93, M = 275)</td><td><bold>499</bold> (A = 74, M = 425)</td></tr><tr><td>Total</td><td>400</td><td>292</td><td>1,020</td><td>566</td></tr><tr><td><italic>Note</italic>. PC = precontemplation; C = contemplation; P = preparation; A = action; M = maintenance; <italic>sensitivity</italic> = Proportion of individuals who were active according to the stage classification among all individuals meeting public health guidelines. <italic>specificity</italic> = Proportion of individuals who were inactive according to the stage classification among all individuals not meeting public health guidelines.</td></tr><tr><td><sup>a</sup> specificity = 277/400 = 69.3%, sensitivity = 241/292 = 82.5%.</td></tr><tr><td><sup>b</sup> specificity = 652/1020 = 63.9%, sensitivity = 499/566 = 88.2%.</td></tr></tbody></table> </ephtml> </p> <hd id="AN0024951643-11">Stage Distribution</hd> <p>Based on the staging questions, in the Type 1 diabetes group, 81 (11.7%) were in precontemplation, 105 (15.2%) in contemplation, 142 (20.5%) in preparation, 69 (10%) in action, and 294 (42.5%) in maintenance. In the Type 2 group, 181 (11.4%) were in precontemplation, 245 (15.4%) in contemplation, 293 (18.5%) in preparation, 167 (10.5%) in action, and 701 (44.2%) in maintenance. The stage distribution pattern between the two diabetes groups was not significantly different, χ<sups>2</sups> (<reflink idref="bib4" id="ref57">4</reflink>, _I_N_i_ = 2,<reflink idref="bib278" id="ref58">278</reflink>) = 0.81, <emph>p</emph> = .53.</p> <hd id="AN0024951643-12">Objective a: Specificity and Sensitivity</hd> <p>The GLTEQ PA measure was used to categorize individuals as meeting, or not meeting, the Canadian Public Health Guidelines. Overall, 57.8% and 64.3% individuals with Type 1 and Type 2 diabetes did not meet the Canadian Public Health Guidelines. Individuals classified as <emph>active</emph> and <emph>inactive</emph> based on the Canadian Public Health Guidelines, as well as stages of change, are displayed in Table 2. The specificity for Type 1 was 69.3% and the sensitivity was 82.5%. In the Type 2 group, specificity and sensitivity were 63.9% and 88.2%, respectively. Thus, the sensitivity was greater than the specificity in both diabetes groups. In comparing the Type 1 and Type 2 groups, it was revealed that specificity and sensitivity values were not significantly different between the two diabetes groups; that is, inactive study participants, χ<sups>2</sups> (<reflink idref="bib4" id="ref59">4</reflink>, _I_N_i_ = 1420) = 4.24, <emph>p</emph> = .38, versus active study participants, χ<sups>2</sups> (<reflink idref="bib4" id="ref60">4</reflink>, _I_N_i_ = 858) = 8.93, <emph>p</emph> = .06.</p> <hd id="AN0024951643-13">Objective b: PA Behavior and Intention Patterns of Different Intensities Across TTM Stages</hd> <p>The means of the stage groups and the results of the planned contrast between adjacent stages are reported in Table 3.</p> <p>TABLE 3. Stages of Change: Means, Standard Deviations, and Planned Comparisons Between Adjacent Stages</p> <p> <ephtml> <table><thead valign="bottom"><tr><td /><td>Precontemplation</td><td>Contemplation</td><td>Preparation</td><td>Action</td><td>Maintenance</td><td>Hypothesized Significant Comparison</td><td>Empirical Significant Comparison</td></tr><tr><td>Sample</td><td>M</td><td>SD</td><td>M</td><td>SD</td><td>M</td><td>SD</td><td>M</td><td>SD</td><td>M</td><td>SD</td></tr></thead><tbody><tr><td>Type 1 diabetes</td><td /><td /><td /><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>Vigorous + moderate activity index score MET minutes</td><td char=".">250.96</td><td char=".">268.32</td><td char=".">325.09</td><td char=".">514.81</td><td char=".">420.59</td><td char=".">581.57</td><td char=".">912.59</td><td char=".">836.15</td><td char=".">1,295.38</td><td char=".">1,426.69</td><td>P < A</td><td>P < A</td></tr><tr><td>Vigorous activity MET minutes</td><td char=".">88.63</td><td char=".">137.98</td><td char=".">36.53</td><td char=".">439.53</td><td char=".">168.49</td><td char=".">369.56</td><td char=".">486.98</td><td char=".">705.96</td><td char=".">653.92</td><td char=".">1,109.50</td><td>P < A</td><td>—</td></tr><tr><td>Moderate activity MET minutes</td><td char=".">162.32</td><td char=".">192.13</td><td char=".">188.56</td><td char=".">194.75</td><td char=".">252.10</td><td char=".">321.97</td><td char=".">425.61</td><td char=".">388.73</td><td char=".">641.46</td><td char=".">868.66</td><td>P < A</td><td>—</td></tr><tr><td>Mild activity MET minutes</td><td char=".">291.39</td><td char=".">386.96</td><td char=".">265.47</td><td char=".">422.90</td><td char=".">385.79</td><td char=".">551.44</td><td char=".">361.21</td><td char=".">344.90</td><td char=".">507.48</td><td char=".">759.78</td><td>—</td><td>—</td></tr><tr><td>Intention</td><td char=".">29.25</td><td char=".">26.10</td><td char=".">46.48</td><td char=".">22.06</td><td char=".">71.76</td><td char=".">19.36</td><td char=".">78.26</td><td char=".">16.71</td><td char=".">90.13</td><td char=".">11.37</td><td>PC < CC < P</td><td>PC < CC < PA < M</td></tr><tr><td>Type 2 diabetes</td><td /><td /><td /><td /><td /><td /><td /><td /><td /><td /><td /><td /></tr><tr><td>Vigorous + moderate activity index score MET minutes</td><td char=".">287.44</td><td char=".">420.32</td><td char=".">258.42</td><td char=".">322.53</td><td char=".">314.69</td><td char=".">367.09</td><td char=".">807.75</td><td char=".">1,513.67</td><td char=".">1,087.82</td><td char=".">1,471.38</td><td>P < A</td><td>P < AA < M</td></tr><tr><td>Vigorous activity MET minutes</td><td char=".">110.21</td><td char=".">282.75</td><td char=".">91.93</td><td char=".">190.37</td><td char=".">100.87</td><td char=".">185.24</td><td char=".">352.53</td><td char=".">1,074.99</td><td char=".">444.66</td><td char=".">1,281.77</td><td>P < A</td><td>—</td></tr><tr><td>Moderate activity MET minutes</td><td char=".">177.23</td><td char=".">219.41</td><td char=".">166.49</td><td char=".">207.65</td><td char=".">213.82</td><td char=".">264.76</td><td char=".">455.21</td><td char=".">541.76</td><td char=".">642.42</td><td char=".">771.77</td><td>P < A</td><td>P < AA < M</td></tr><tr><td>Mild activity MET minutes</td><td char=".">320.66</td><td char=".">761.72</td><td char=".">290.29</td><td char=".">664.87</td><td char=".">287.23</td><td char=".">463.18</td><td char=".">479.15</td><td char=".">854.95</td><td char=".">527.51</td><td char=".">664.06</td><td>—</td><td>P < A</td></tr><tr><td>Intention</td><td char=".">25.35</td><td char=".">26.33</td><td char=".">49.47</td><td char=".">21.40</td><td char=".">67.68</td><td char=".">21.30</td><td char=".">76.35</td><td char=".">17.51</td><td char=".">86.51</td><td char=".">15.43</td><td>PC < CC < P</td><td>PC < CC < PP < AA < M</td></tr><tr><td><italic>Note</italic>. MET = metabolic equivalent; PC = precontemplation; C = contemplation; P = preparation; A = action; M = maintenance; < = a significant difference between the indicated stages; if no such difference is reported, no significant pair comparison was hypothesized.</td></tr></tbody></table> </ephtml> </p> <p>For behavior, the only predicted significant difference found in the Type 1 diabetes group was for combined moderate–vigorous activity, whereas those in action were more active than individuals in preparation. Although the same trend was found for other intensities of behavior, the differences did not reach statistical significance. In the Type 2 group, preparation and action reported significantly different means in moderate and combined moderate–vigorous activity, but not in vigorous activity. Intention significantly increased from precontemplation to contemplation, from contemplation to preparation, and from action to maintenance in both diabetes groups. Intention also increased from preparation to action in the Type 2 diabetes group.</p> <hd id="AN0024951643-14">Objective c: Age Differences</hd> <p>Because there were no significant differences between Type 1 and Type 2 diabetic individuals (in terms of PA measures and intention), both groups were combined, and age differences in PA measured with the GLTEQ ([<reflink idref="bib15" id="ref61">15</reflink>]) across the stages were examined. The means of combined moderate–vigorous PA and means of mild activity are displayed in Figures 1 and 2, respectively.</p> <p>Graph</p> <p>Graph</p> <p>In examining combined moderate–vigorous activity, all age groups in precontemplation, contemplation, and preparation reported lower levels of activity than those in action and maintenance; however, this was only statistically significant for individuals in the 40- to 60-year range (40–49 years: Δ<emph>M</emph><subs>P–A</subs><sups>2</sups> = 478.7, <emph>p</emph> = .04; and 50–59 years: Δ<emph>M</emph><subs>P–A</subs><sups>2</sups> = 652.6, <emph>p</emph> <.01). For mild activity (see Figure 2), the older groups (ages ≥ 60 years) displayed a steep increase in their activity patterns (Δ<emph>M</emph><subs>P–A</subs><sups>2</sups> = 218.4, <emph>ns</emph>). The youngest age group in preparation reported more mild activity than all other age groups in that stage (see Table 4).[<reflink idref="bib1" id="ref62">1</reflink>]</p> <p>TABLE 4. Stage Measure Sensitivity and Specificity in Terms of the Canadian Public Health Guidelines for Physical Activity (120 min per week) Differentiated by Age Groups</p> <p> <ephtml> <table><thead valign="bottom"><tr><td /><td>Less Than 40 years</td><td>40 to 49 years</td><td>50 to 59 years</td><td>60 to 69 years</td><td>70 or more years</td></tr><tr><td>Stage</td><td>Inactive</td><td>Active</td><td>Inactive</td><td>Active</td><td>Inactive</td><td>Active</td><td>Inactive</td><td>Active</td><td>Inactive</td><td>Active</td></tr></thead><tbody><tr><td>Inactive according to stage (PC, C, and P)</td><td><bold>88</bold> (PC = 3, C = 35, P = 50)</td><td><bold>32</bold> (PC = 2, C = 11, P = 19)</td><td><bold>130</bold> (PC = 19, C = 57, P = 54)</td><td><bold>21</bold> (PC = 0, C = 4, P = 17)</td><td><bold>232</bold> (PC = 44, C = 77, P = 111)</td><td><bold>22</bold> (PC = 1, C = 9, P = 12)</td><td><bold>206</bold> (PC = 56, C = 63, P = 87)</td><td><bold>25</bold> (PC = 7, C = 6, P = 12)</td><td><bold>273</bold> (PC = 123, C = 84, P = 66)</td><td><bold>18</bold> (PC = 7, C = 4, P = 7)</td></tr><tr><td>Active according to stage (A and M)</td><td><bold>24</bold> (A = 12, M = 12)</td><td><bold>102</bold> (A = 25, M = 77)</td><td><bold>37</bold> (A = 12, M = 25)</td><td><bold>111</bold> (A = 21, M = 90)</td><td><bold>93</bold> (A = 24, M = 69)</td><td><bold>161</bold> (A = 39, M = 122)</td><td><bold>126</bold> (A = 39, M = 87)</td><td><bold>210</bold> (A = 19, M = 191)</td><td><bold>211</bold> (A = 36, M = 175)</td><td><bold>156</bold> (A = 9, M = 147)</td></tr><tr><td>Total</td><td>112</td><td>134</td><td>167</td><td>132</td><td>325</td><td>183</td><td>332</td><td>235</td><td>484</td><td>174</td></tr><tr><td><italic>Note</italic>. PC = Precontemplation; C = Contemplation; P = Preparation; A = Action; M = Maintenance. <italic>sensitivity</italic> = Proportion of individuals who were active according to the stage classification among all individuals meeting public health guidelines. <italic>specificity</italic> = Proportion of individuals who were inactive according to the stage classification among all individuals not meeting public health guidelines.</td></tr><tr><td><sup>a</sup> specificity = 88/112 = 78.6%, sensitivity = 102/134 = 76.1%.</td></tr><tr><td><sup>b</sup> specificity = 130/167 = 77.8%, sensitivity = 111/132 = 84.1%.</td></tr><tr><td><sup>c</sup> specificity = 232/325 = 71.4%, sensitivity = 161/183 = 88.0%.</td></tr><tr><td><sup>d</sup> specificity = 206/332 = 62.0%, sensitivity = 210/235 = 89.4%.</td></tr><tr><td><sup>e</sup> specificity = 273/484 = 56.4%, sensitivity = 156/174 = 89.7%.</td></tr></tbody></table> </ephtml> </p> <p>Specificity was higher for the younger age groups; that is 78.6% (< 40 years), 77.8% (40–49 years), 71.4% (50–59 years), 62.0% (60–69 years), and 56.4% (≥ 70 years). Sensitivity was higher for the older age groups (i.e., 76.1%, 84.1%, 88.0%, 89.4%, and 89.7% for the respective age groups). These results indicate an increasing trend in sensitivity with increasing age. Alternatively, specificity decreased as participants' age increased (see Table 4).</p> <hd id="AN0024951643-15">Subsidiary Objective: Explained Variances by Stage, Age, and Diabetes Type</hd> <p>MANOVAs were computed including stage, age, and diabetes type as factors and PA behavior and intention as dependent variables (as detailed in the Method section). Stage explained more variance than age and diabetes type. Stage explained 2% to 36% of behavior and intentions variance: vigorous PA (<emph>R</emph><sups>2</sups> = .02), moderate PA (<emph>R</emph><sups>2</sups> = .07), mild PA (<emph>R</emph><sups>2</sups> = .03), combined moderate–vigorous PA (<emph>R</emph><sups>2</sups> = .08), and intention (<emph>R</emph><sups>2</sups> = .36), all <emph>p</emph>s <.01.</p> <p>Age explained less variance and was only significant for combined moderate–vigorous PA (<emph>R</emph><sups>2</sups> = .01) and intention (<emph>R</emph><sups>2</sups> = .01). Type of diabetes was not significant (all <emph>p</emph>s = .25) with all of the variables and explained less than 0.1% of the variances. In summary, stage shared more variance (i.e., has more in common) with PA behavior and intention than did age and type of diabetes.</p> <hd id="AN0024951643-16">DISCUSSION</hd> <p>According to the literature, theory-based interventions are more effective than aetheoretical approaches for promoting PA ([<reflink idref="bib12" id="ref63">12</reflink>]). Considering the TTM's popularity for promoting regular PA and active lifestyle adoption and adherence ([<reflink idref="bib8" id="ref64">8</reflink>]; [<reflink idref="bib18" id="ref65">18</reflink>]; [<reflink idref="bib23" id="ref66">23</reflink>]), we have attempted to provide evidence for the validity of a standard PA TTM stage algorithm in individuals with diabetes. The results of this study add to the current literature of one of the most comprehensive and rigorous examinations on this topic to date by assessing a large population-based sample of individuals with both Type 1 or Type 2 diabetes. To our knowledge, this is the first study to test diabetes group differences for intentions and behavior.</p> <p>Our finding that most adults with diabetes do not regularly engage in PA adequate to achieve health benefits is consistent with findings from other research (i.e., The Canadian National Population Health Survey [[<reflink idref="bib16" id="ref67">16</reflink>]] reported that approximately 60% of people with diabetes ages 35–64 years and 76% of those > 65 years of age are inactive).</p> <hd id="AN0024951643-17">Specificity and Sensitivity</hd> <p>This study's specificity results are comparable to those reported in other studies that have assessed the TTM's staging measure with of PA in the general population, in which on average, specificity has been reported to be approximately 67% ([<reflink idref="bib23" id="ref68">23</reflink>]). Our sensitivity results were higher than the average of studies reported to date (<emph>M</emph> = 78.5%). However, it should be noted that Nigg employed a different measure of PA, and this may explain the difference. When comparing sensitivity and specificity values for the two diabetes groups, no significant differences emerged.</p> <hd id="AN0024951643-18">Validating the Stage Measure with Different Intensities of Behavior</hd> <p>The trend toward higher self-reported activity levels across the stages of change observed for both Type 1 and Type 2 individuals was an expected finding. For the Type 1 diabetes group, the expected significant difference between preparation and action stages was only observed for the combined moderate–vigorous PA.</p> <p>Moderate PA of individuals in action was significantly higher than those in preparation for Type 1 individuals. This was not observed for the Type 2 group. Based on previous findings ([<reflink idref="bib23" id="ref69">23</reflink>]), we hypothesized that mild activity would be similar for the preparation and action stages; however, this was only found to be true in the Type 1 group. In the Type 2 group, individuals in action performed more mild activity than those in preparation. Considering that the Type 2 participants in our sample were significantly older than the Type 1 participants, this result is in line with a study by [<reflink idref="bib35" id="ref70">35</reflink>] in which the same result was found for the oldest subsample. In summary, 31 out of 40 (77.5%) of the predictions (reported to be significantly different or not) between adjacent stages (i.e., precontemplation–contemplation, contemplation–preparation, preparation–action, and action–maintenance) were correct (see Table 3).</p> <hd id="AN0024951643-19">Validating the Stage Measure with Intention</hd> <p>The significant increase in the mean level of intention from precontemplation to contemplation and from contemplation to preparation is in line with theoretical predictions and empirical evidence presented previously. However, intention increased from preparation to action in the Type 2 diabetes group and from action to maintenance in both diabetes groups, which was an unexpected finding.</p> <hd id="AN0024951643-20">Age Differences</hd> <p>Age was a significant factor in explaining the variance in combined moderate–vigorous activity and intention. The age distribution patterns observed for different intensities of PA are consistent with other studies that investigated age differences using comparable measures (e.g., [<reflink idref="bib38" id="ref71">38</reflink>]). With increasing age, it was noted that specificity is lower and sensitivity is higher. Furthermore, younger individuals in preparation seem to value moderate activities as "preparatory behavior" rather than goal behavior. Alternatively, older individuals in preparation tend to include mild activities as goal behavior instead of vigorous and moderate PA behavior. The older population also tends to judge participation in moderate activities as vigorous.</p> <hd id="AN0024951643-21">Explained Variances of Stage, Age, and Diabetes Type</hd> <p>Stage significantly differentiated vigorous, moderate, mild, and combined moderate–vigorous activity; albeit the <emph>R</emph><sups>2</sups> values were relatively small (the explained variance for intention, however, was relatively large, accounting for 36% of the variance). Furthermore, diabetes type was not a significant factor in explaining variance for intention and the different PA intensities. Moreover, in relation to the results of stage and age, type of diabetes was negligible in its explanatory ability.</p> <hd id="AN0024951643-22">Summary and Future Directions</hd> <p>Our findings highlight several key considerations for both researchers and health practitioners and provide supportive evidence for the utility of the PA staging measure for the diabetes population. The majority of our hypotheses (26 out of 32 of the tests for behavioral, and 5 out of 8 of the tests for intention) was confirmed. Although specificity was 69.3% and 63.9% and sensitivity was 82.5% and 88.2%, respectively, for the Type 1 and Type 2 groups, ideally specificity and sensitivity should be 100%. Future researchers should investigate modified versions of the stage measure (e.g., without time referents) to improve the validity of the measure (i.e., a stage measure that would more accurately classify individuals as either meeting, or not meeting, PA guidelines).</p> <p>Although diabetes type is somewhat worthy to consider for PA stage classification, age appears to be a stronger significant contributing factor. Further research and practice considerations must be given to older adults (i.e., ≥ 50 years) who are performing milder intensity levels. From a population perspective, a greater proportion of older adults may be achieving public health guidelines in relative, versus absolute, terms.</p> <p>This study uses the Canadian Public Health Guidelines of achieving at least 120 min of moderate intensity PA per week as a threshold to calculate specificity and sensitivity of TTM. It should be noted that U.S. public health guidelines specify a minimum of 150 min of moderate intensity per week of activity ([<reflink idref="bib24" id="ref72">24</reflink>]), and if this measure had been used, we may have obtained different results. The continued examination of TTM across various intensities could inform us in developing activity guidelines for different age groups of the diabetic population.</p> <p>Strengths of this study include the large sample employed and using scores on intention with different intensities of PA to validate TTM. Limitations of this study include using only a single measure to assess intention and the reliance on self-reports of PA. These limitations should be addressed by future researchers.</p> <hd id="AN0024951643-23">ACKNOWLEDGEMENTS</hd> <p>The first author is supported by Salary Awards from the Alberta Heritage Foundation for Medical Research and the Canadian Institutes for Health Research (CIHR). The second author was funded through a CIHR New Emerging Team Grant during the time of this research. The fourth author is supported by the Canadian Research Chair Program. The sixth author is funded by the Ontario Ministry of Health, Scientist Career Award. We would like to thank Kylie Hugo for her editorial assistance on this manuscript.</p> <ref id="AN0024951643-24"> <title> Footnotes </title> <blist> <bibl id="bib1" idref="ref10" type="bt">1</bibl> <bibtext> ΔM = mean difference between adjacent stage groups, i.e. Preparation and Action.</bibtext> </blist> <blist> <bibl id="bib2" idref="ref8" type="bt">2</bibl> <bibtext> Brug, J., Conner, M., Harre, N., Kremers, S., McKellar, S., & Whitelaw, S. (2005). The transtheoretical model and stages of change: A critique. Observations by five commentators on the paper by Adams, J. and White, M. (2004): Why don't stage-based activity promotion interventions work? <emph>Health Education Research</emph>, 20, 244–258.</bibtext> </blist> <blist> <bibl id="bib3" idref="ref15" type="bt">3</bibl> <bibtext> Statistics Canada. (2001). Census 2001-2B Ottawa, Ontario, Heath Canada,(pp. 1–32).</bibtext> </blist> <blist> <bibl id="bib4" idref="ref43" type="bt">4</bibl> <bibtext> 600 MET/Week is equivalent to 150 minutes of moderate physical activity/Week ([4])</bibtext> </blist> </ref> <ref id="AN0024951643-25"> <title> REFERENCES </title> <blist> <bibtext> Adams, J. and White, M. 2004. Why don't stage-based activity promotion interventions work?. Health Education Research, 20 : 237 – 243.</bibtext> </blist> <blist> <bibtext> Ainsworth, B. E., Haskell, W. L., Whitt, M. C., Irwin, M. L., Swartz, A. M. Strath, S. J. 2000. Compendium of physical activities: An update of activity codes and MET intensities. Medicine & Science in Sports & Exercise, 32 (9 Suppl) : S498 – 504.</bibtext> </blist> <blist> <bibtext> Battista, J., Nigg, C. R., Chang, J., Yamashita, M. and Chung, R. 2004. Getting children physically active: Opportunities and mechanisms. Journal of Sport and Exercise Psychology, 26 : S31</bibtext> </blist> <blist> <bibtext> Brown, W. J. and Bauman, A. E. 2000. Comparison of estimates of population levels of physical activity using two measures. Australia and New Zealand Journal of Public Health, 24 : 520 – 525.</bibtext> </blist> <blist> <bibl id="bib5" idref="ref7" type="bt">5</bibl> <bibtext> Burkholder, G. J. and Evers, K. A. 2002. " Application of the Transtheoretical Model to Several Problem Behaviors ". In Promoting exercise and behavior change in older adults: Interventions with the transtheoretical model, Edited by: Burbank, P. and Riebe, D. 85 – 146. New York : Springer.</bibtext> </blist> <blist> <bibl id="bib6" idref="ref1" type="bt">6</bibl> <bibtext> Canadian Diabetes Association. (2003). Clinical practice guidelines. <ulink href="http://www.diabetes.ca/cpg2003/download.aspx">http://www.diabetes.ca/cpg2003/download.aspx</ulink> (Accessed: 2 June 2005).</bibtext> </blist> <blist> <bibl id="bib7" idref="ref36" type="bt">7</bibl> <bibtext> Courneya, K. S., Jones, L. W., Rhodes, R. E. and Blanchard, C. M. 2004. Effects of different combinations of intensity categories on self-reported exercise. Research Quarterly for Exercise and Sport, 75 (4) : 429 – 433.</bibtext> </blist> <blist> <bibl id="bib8" idref="ref64" type="bt">8</bibl> <bibtext> Courneya, K. S., Estabrooks, P. A. and Nigg, C. R. 1997. A simple reinforcementstrategy for increasing attendance at a fitness facility. Health Education & Behavior, 24 : 708 – 715.</bibtext> </blist> <blist> <bibl id="bib9" idref="ref14" type="bt">9</bibl> <bibtext> Courneya, K. S., Nigg, C. R. and Estabrooks, P. A. 1998. Relationships among the theory of planned behavior, stages of change, and exercise behavior in older persons over a three-year period. Psychology & Health, 13 : 355 – 367.</bibtext> </blist> <blist> <bibtext> Courneya, K., Plotnikoff, R., Hotz, S. and Birkett, N. 2001. Predicting exercise stage transitions over two consecutive 6-month periods: A test of the theory of planned behaviour in a population-based sample. British Journal of Health Psychology, 6 : 135 – 150.</bibtext> </blist> <blist> <bibtext> Dannecker, E. A., Hausenblas, H. A., Connaughton, D. P. and Lovins, T. R. 2003. Validation of a stage of change questionnaire. Research Quarterly for Exercise and Sport, 74 : 236 – 247.</bibtext> </blist> <blist> <bibtext> Dishman, R. K. and Buckworth, J. 1996. Increasing physical activity: A quantitative synthesis. Medical Science in Sports and Exercise, 28 : 706 – 719.</bibtext> </blist> <blist> <bibtext> Espallardo, N. L. 2003. Decisions on diagnosis in family practice: Use of sensitivity, specificity, predictive values and likelihood ratios. Asia Pacific Family Medicine, 2 : 229 – 232.</bibtext> </blist> <blist> <bibtext> Garner, C. and Page, S. J. 2005. Applying the transtheoretical model to the exercise behaviors of stroke patients. Topics in Stroke Rehabilitation, 12 : 69 – 75.</bibtext> </blist> <blist> <bibtext> Godin, G. and Shephard, R. J. 1985. A simple method to assess exercise behavior in the community. Canadian Journal of Applied Sport Sciences, 10 : 141 – 146.</bibtext> </blist> <blist> <bibtext> Health Canada. 1999. Diabetes in Canada: National statistics and opportunities for improved surveillance, Diabetes Division, Bureau of Cardio-Respiratory Diseases and Diabetes, Laboratory Centre for Disease Control, Health Protection Branch 1 – 69. Ottawa, Ontario,, Canada</bibtext> </blist> <blist> <bibtext> Jacobs, D. R., Ainsworth, B. E., Hartman, T. J. and Leon, A. S. 1993. A simultaneous evaluation of 10 commonly used physical activity questionnaires. Medical Science in Sports and Exercise, 25 : 81 – 91.</bibtext> </blist> <blist> <bibtext> Jones, N. D., DellaCorte, M. R., Nigg, C. R., Clark, P. G., Burbank, P. M. and Garber, C. E. 2001. Seniorcise: A print exercise intervention in older adults. Educational Gerontology, 27 : 717 – 728.</bibtext> </blist> <blist> <bibtext> Lee, R. E., Nigg, C. R., DiClemente, C. C. and Courneya, K. S. 2001. Validating motivational readiness for exercise behavior with adolescents. Research Quarterly for Exercise and Sport, 72 : 401 – 410.</bibtext> </blist> <blist> <bibtext> Marcus, B. H., Rossi, J. S., Selby, V. C., Niaura, R. S. and Abrams, D. B. 1992. The stages and processes of exercise adoption and maintenance in a worksite sample. Health Psychology, 11 : 386 – 395.</bibtext> </blist> <blist> <bibtext> Marcus, B. H., Selby, V. C., Niaura, R. S. and Rossi, J. S. 1992. Self-efficacy and the stages of exercise behavior change. Research Quarterly for Exercise & Sport, 63 : 60 – 66.</bibtext> </blist> <blist> <bibtext> Marcus, B. H., Simkin, L. R., Rossi, J. S. and Pinto, B. M. 1996. Longitudinal shifts in employee's stages and processes of exercise behavior change. American Journal of Health Promotion, 10 : 195 – 200.</bibtext> </blist> <blist> <bibtext> Nigg, C. R. 2005. There is more to stages of exercise than just exercise. American College of Sports Medicine, 33 : 32 – 35.</bibtext> </blist> <blist> <bibtext> Pate, R. R., Pratt, M., Blair, S. N., Haskell, W. L., Macera, C. A. Bouchard, C. 1995. Physical activity and public health: A recommendation from the Centers for Disease Control and Prevention and the American College of Sports Medicine. Journal of the American Medical Association, 273 : 402 – 407.</bibtext> </blist> <blist> <bibtext> Plotnikoff, R. 2006. Physical activity in the management of diabetes: Population-based issues and approaches. Canadian Journal of Diabetes, 30 (1) : 52 – 62.</bibtext> </blist> <blist> <bibtext> Plotnikoff, R., Brez, S. and Brunet, S. 2003. Are exercise social-cognitive factors and behaviors different for adults with diabetes? A randomized community sample. Psychology, Health & Medicine, 8 : 465 – 471.</bibtext> </blist> <blist> <bibtext> Plotnikoff, R., Brez, S. and Hotz, S. B. 2000. Exercise behavior in a community sample with diabetes: Understanding the determinants of exercise behavioral change. Diabetes Educator, 26 : 450 – 459.</bibtext> </blist> <blist> <bibtext> Plotnikoff, R. and Higginbotham, N. 1998. Protection motivation theory and the prediction of exercise and low-fat diet behaviours among Australian cardiac patients. Psychology & Health, 13 : 411 – 429.</bibtext> </blist> <blist> <bibtext> Plotnikoff, R. and Higginbotham, N. 2002. Protection motivation theory and exercise behavior change for the prevention of coronary heart disease in a high-risk, Australian representative community sample of adults. Psychology, Health & Medicine, 7 (1) : 87 – 98.</bibtext> </blist> <blist> <bibtext> Plotnikoff, R., Hotz, S. B., Birkett, N. J. and Courneya, K. S. 2001. Exercise and the transtheoretical model: A longitudinal test of a population sample. Preventive Medicine, 33 : 441 – 452.</bibtext> </blist> <blist> <bibtext> Plotnikoff, R., Taylor, L., Wilson, P., Courneya, K., Sigal, R., Birkett, N., Raine, K. and Svenson, L. 2006. Factors associated with physical activity in Canadian adults with diabetes medicine and science in sports and exercise. 38 (8) : 1526 – 1534.</bibtext> </blist> <blist> <bibtext> Prochaska, J. O. and DiClemente, C. C. 1983. Stages and process of self-change in smoking: Towards an integrative model of change. Journal of Consulting and Clinical Psychology, 51 : 390 – 395.</bibtext> </blist> <blist> <bibtext> Riemsma, R. P., Pattenden, J., Bridle, C., Sowden, A. J., Mather, L. Watt, I. S. 2003. Systematic review of the effectiveness of stage based interventions to promote smoking cessation. The British Medical Journal, 326 (7400) : 1175 – 1177.</bibtext> </blist> <blist> <bibtext> Sarkin, J. A., Johnson, S. S., Prochaska, J. O. and Prochaska, J. M. 2001. Applying the transtheoretical model to regular moderate exercise in an overweight population: Validation of a stage of change measure. Preventive Medicine, 33 : 462 – 469.</bibtext> </blist> <blist> <bibtext> Schumann, A., Estabrooks, P. A., Nigg, C. R. and Hill, J. 2003. Validation of the stages of change with mild, moderate, and strenuous physical activity behavior, intentions, and self-efficacy. International Journal of Sports Medicine, 5 : 363 – 365.</bibtext> </blist> <blist> <bibtext> Sigal, R. J., Kenny, G. P., Wasserman, D. H. and Castaneda-Sceppa, C. 2003. Canadian Diabetes Association 2003 clinical practice guidelines for the prevention and management of diabetes in Canada. Canadian Journal of Diabetes, 27 : S24 – S26.</bibtext> </blist> <blist> <bibtext> Tabachnick, B. G. and Fidell, L. S. 2001. Using multivariate statistics, Needham Heights, MA : Allyn & Bacon.</bibtext> </blist> <blist> <bibtext> Ziegelmann, J. P., Lippke, S. and Schwarzer, R. 2006. Adoption and maintenance of physical activity: Planning interventions in young, middle-aged, and older adults. Psychology & Health, 21 : 145 – 163.</bibtext> </blist> </ref> <aug> <p>By RonaldC. Plotnikoff; Sonia Lippke; Melissa Reinbold-Matthews; KerryS. Courneya; Nandini Karunamuni; RonaldJ. Sigal and Nicholas Birkett</p> <p>Reported by Author; Author; Author; Author; Author; Author; Author</p> </aug> <nolink nlid="nl1" bibid="bib16" firstref="ref2"></nolink> <nolink nlid="nl2" bibid="bib36" firstref="ref3"></nolink> <nolink nlid="nl3" bibid="bib25" firstref="ref4"></nolink> <nolink nlid="nl4" bibid="bib32" firstref="ref5"></nolink> <nolink nlid="nl5" bibid="bib23" firstref="ref6"></nolink> <nolink nlid="nl6" bibid="bib33" firstref="ref11"></nolink> <nolink nlid="nl7" bibid="bib11" firstref="ref17"></nolink> <nolink nlid="nl8" bibid="bib19" firstref="ref18"></nolink> <nolink nlid="nl9" bibid="bib34" firstref="ref19"></nolink> <nolink nlid="nl10" bibid="bib35" firstref="ref20"></nolink> <nolink nlid="nl11" bibid="bib14" firstref="ref24"></nolink> <nolink nlid="nl12" bibid="bib22" firstref="ref25"></nolink> <nolink nlid="nl13" bibid="bib26" firstref="ref34"></nolink> <nolink nlid="nl14" bibid="bib27" firstref="ref35"></nolink> <nolink nlid="nl15" bibid="bib15" firstref="ref37"></nolink> <nolink nlid="nl16" bibid="bib17" firstref="ref39"></nolink> <nolink nlid="nl17" bibid="bib30" firstref="ref47"></nolink> <nolink nlid="nl18" bibid="bib20" firstref="ref48"></nolink> <nolink nlid="nl19" bibid="bib21" firstref="ref49"></nolink> <nolink nlid="nl20" bibid="bib10" firstref="ref50"></nolink> <nolink nlid="nl21" bibid="bib28" firstref="ref51"></nolink> <nolink nlid="nl22" bibid="bib29" firstref="ref52"></nolink> <nolink nlid="nl23" bibid="bib37" firstref="ref54"></nolink> <nolink nlid="nl24" bibid="bib13" firstref="ref55"></nolink> <nolink nlid="nl25" bibid="bib278" firstref="ref58"></nolink> <nolink nlid="nl26" bibid="bib12" firstref="ref63"></nolink> <nolink nlid="nl27" bibid="bib18" firstref="ref65"></nolink> <nolink nlid="nl28" bibid="bib38" firstref="ref71"></nolink> <nolink nlid="nl29" bibid="bib24" firstref="ref72"></nolink>
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  Data: Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals with Type 1 or Type 2 Diabetes
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  Data: <searchLink fieldCode="AR" term="%22Plotnikoff%2C+Ronald+C%2E%22">Plotnikoff, Ronald C.</searchLink><br /><searchLink fieldCode="AR" term="%22Lippke%2C+Sonia%22">Lippke, Sonia</searchLink><br /><searchLink fieldCode="AR" term="%22Reinbold-Matthews%2C+Melissa%22">Reinbold-Matthews, Melissa</searchLink><br /><searchLink fieldCode="AR" term="%22Courneya%2C+Kerry+S%2E%22">Courneya, Kerry S.</searchLink><br /><searchLink fieldCode="AR" term="%22Karunamuni%2C+Nandini%22">Karunamuni, Nandini</searchLink><br /><searchLink fieldCode="AR" term="%22Sigal%2C+Ronald+J%2E%22">Sigal, Ronald J.</searchLink><br /><searchLink fieldCode="AR" term="%22Birkett%2C+Nicholas%22">Birkett, Nicholas</searchLink>
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  Data: <searchLink fieldCode="SO" term="%22Measurement+in+Physical+Education+and+Exercise+Science%22"><i>Measurement in Physical Education and Exercise Science</i></searchLink>. Apr 2007 11(2):73-91.
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  Data: Routledge. Available from: Taylor & Francis, Ltd. 325 Chestnut Street Suite 800, Philadelphia, PA 19106. Tel: 800-354-1420; Fax: 215-625-2940; Web site: http://www.tandf.co.uk/journals
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  Data: 19
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  Data: Journal Articles<br />Reports - Evaluative
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  Data: <searchLink fieldCode="DE" term="%22Physical+Activities%22">Physical Activities</searchLink><br /><searchLink fieldCode="DE" term="%22Physical+Activity+Level%22">Physical Activity Level</searchLink><br /><searchLink fieldCode="DE" term="%22Diabetes%22">Diabetes</searchLink><br /><searchLink fieldCode="DE" term="%22Validity%22">Validity</searchLink><br /><searchLink fieldCode="DE" term="%22Intention%22">Intention</searchLink><br /><searchLink fieldCode="DE" term="%22Foreign+Countries%22">Foreign Countries</searchLink><br /><searchLink fieldCode="DE" term="%22Measures+%28Individuals%29%22">Measures (Individuals)</searchLink><br /><searchLink fieldCode="DE" term="%22Guidelines%22">Guidelines</searchLink><br /><searchLink fieldCode="DE" term="%22Health+Behavior%22">Health Behavior</searchLink><br /><searchLink fieldCode="DE" term="%22Age+Differences%22">Age Differences</searchLink><br /><searchLink fieldCode="DE" term="%22Behavior+Patterns%22">Behavior Patterns</searchLink>
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  Data: <searchLink fieldCode="DE" term="%22Canada%22">Canada</searchLink>
– Name: DOI
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  Data: 10.1080/10913670701294062
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  Data: 1091-367X
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  Label: Abstract
  Group: Ab
  Data: This study was designed to test the validity of a transtheoretical model's physical activity (PA) stage measure with intention and different intensities of behavior in a large population-based sample of adults living with diabetes (Type 1 diabetes, n = 697; Type 2 diabetes, n = 1,614) and examine different age groups. The overall "specificity" (classified correctly as inactive) for Type 1 diabetes was 69.3% based on the percentage of individuals in precontemplation, contemplation, and preparation not meeting Canada's PA guidelines. "Sensitivity" (classified correctly as active) was 82.5% based on the proportion of active participants in action and maintenance. In the Type 2 diabetes group, the overall specificity and sensitivity was 63.9% and 88.2%, respectively. No significant differences were found between the diabetes groups for stage distribution patterns, and sensitivity and specificity values. The majority of the study hypotheses related to intention and behaviors were confirmed, providing further supportive evidence for the utility of this PA staging measure for the diabetes population. (Contains 2 figures, 4 tables and 2 footnotes.)
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  Data: 2009
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        Type: general
      – SubjectFull: Physical Activity Level
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      – SubjectFull: Diabetes
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      – TitleFull: Assessing the Validity of a Stage Measure on Physical Activity in a Population-Based Sample of Individuals with Type 1 or Type 2 Diabetes
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