Health services research in the public healthcare system in Hong Kong: an analysis of over 1 million antihypertensive prescriptions between 2004-2007 as an example of the potential and pitfalls of using routinely collected electronic patient data. - Wong MC; Jiang JY; Tang JL; Lam A; Fung H; Mercer SW; Wong, Martin C S; Jiang, Johnny Y; Tang, Jin-ling; Lam, Augustine; Fung, Hong; Mercer, Stewart W (BMC Health Services Research, 2008)