Table 3.

Sample and response rates of the pilot studies on household level

	Pilot study 1			Pilot study 2
Households in %	Overall (n = 300)	TD (n = 100)	AD (n = 200)	Overall (n = 145)	TD (n = 49)	AD (n = 96)
Recruitment phase
Gross sample size	100	100	100	100	100	100
Not availablea	35	35	35	29	30	29
Participation rejected	27	33	24	42	43	42
Participation agreed: households received questionnaires	38 (n = 114)	32 (n = 32)	41 (n = 82)	28 (n = 41)	27 (n = 13)	29 (n = 28)
Questionnaire phase
Households returned questionnairesb	73	81	70	68	62	71
Net response of gross sample	28	26	29	19	16	21

^aNo phone number, not in target area, failed to contact, no communication possible

^bPercentages based on households which received questionnaires