Detecting referral and selection bias by the anonymous linkage of practice, hospital and clinic data using Secure and Private Record Linkage (SAPREL): case study from the evaluation of the Improved Access to Psychological Therapy (IAPT) service

Table 2 Comparison by gender of practice list, using hospital services, common mental health problems (CMHP), referred to IAPT and part of the in-depth evaluation cohort

	In-depth study cohort	IAPT referrals	CMHP	Use hospital services	Practice list
Female	123	734	8229	33785	75523
	74.10%	65.70%	67.40%	56.00%	49.60%
Male	43	384	3981	26457	76779
	25.90%	34.30%	32.60%	44.00%	50.40%
Total	166	1118	12210	60143	152302
	100%	100%	100%	100%	100%
	Pearson X²	Pearson X²	Pearson X²	Pearson X²	NPar X²
	p< 0.001	p = 0.023	p< 0.001	p< 0.001	p = 0.016

ISSN: 1472-6947