Table 2.

Variable definitions and summary statistics

Variable name	Variable definition	Mean (SD)	Range	Data source
Cost	Net ingredient costs per capita	83.34 (20.39)	9.36-219.28	Prescription Pricing Authority
ASTRO(97)-PU*	ASTRO(97)-PUs per capita	4.24 (0.62)	1.63-8.51	Prescribing Support Unit, Leeds
psick	% of adult population in households permanently sick	3.66 (1.76)	0.77-14.51	Small area statistics
pnocare	% of dependants in no carer households	15.06 (3.89)	3.58-38.06	Small area statistics
pstudent	% of working age population who are students	5.12 (1.74)	2.16-21.03	Local base statistics
pbirths†	% of births on practice lists	1.3 (0.4)	0-6.7	Prescription Pricing Authority and Office of National Statistics

^*Age, sex, and temporary resident originated prescribing units. 

^†Estimated as product of proportion of 0-4 year olds on practice list and weighted average of ratios of Office of National Statistics estimate of births to Office of National Statistics estimate of 0-4 year olds for health authorities in which practice has registrations