Kiek Tates*, Marieke Zwaanswijk, Roel Otten, Sandra van Dulmen, Peter M Hoogerbrugge, Willem A Kamps and Jozien M Bensing
* Corresponding author: Kiek Tates k.tates@nivel.nl
BMC Medical Research Methodology 2009, 9:15 doi:10.1186/1471-2288-9-15
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