Procedural experiments

These experiments explore survey design procedures which are intended to reduce non-response or to improve fieldwork efficiency.

Number	Experiment	Wave(s) appeared
7.1	Incentives and response	All
7.2	The use of conditional and unconditional incentives	7
7.3	Mixed mode experiments: telephone and face-to-face	3
7.4	Mixed mode experiments: web and face-to-face	5-11, 15-16
7.5	Paper vs CASI self-completion	4, 5, 6
7.6	Advance materials: letters vs. cards	2
7.7	Advance materials: content of advance letters	5
7.8	Targeted advance letters	6
7.9	Number of mailings between interviews	7
7.10	Different ways of asking respondents to register on participant website	4
7.11	Improving interviewer observations about characteristics of address	4
7.12	Effect of content of re-issue letter on refusal conversion	4
7.13	Early bird scheduling: encouraging respondents to call interviewer to schedule appointment	4
7.14	Targeted weekday invitation emails	9
7.15	Using prospect theory In wording of advance letters	10
7.16	Invitation letters for mixed mode survey	11
7.17	Spending Study 2	11
7.18	Invitation to complete pre-interview blood pressure measure:information treatment vs pro-social appeal	12
7.19	Fieldwork compression experiment	13
7.20	Event triggered data collection	13
7.21	Consent to survey questions by SMS	13,15
7.22	Wellbeing app study	13
7.23	Asking for Living Apart Together partner details	14
7.24	Contact protocols for IP14 refreshment sample	14
7.25	PERKs for unconditional incentives	16
7.26	Youth online survey	16
7.27	Test of Government logo on envelopes for continuing sample	16