Table A2.

Sample sizes, retention rates and response rates at each Time point of the New Zealand Attitudes and Values Study.

	Time 1 (2009)	Time 2 (2010)	Time 3 (2011)	Time 3.5 (2012)	Time 4 (2012)	Time 5 (2013)	Time 6 (2014)	Time 7 (2015)	Time 8 (2016)	Time 9 (2017)
Sample size (N)	6,518	4,441	6,884	4,514	12,179	18,261	15,820	13,942	21,936	17,072
N retained from at least one previous Time point	––-	4,423	3,918	4,090	6,807	10,502	15,740	13,941	13,779	16,931
N retained from previous Time point only	––-	4,423	3,530	––-	5,762	9,844	14,878	12,550	11,933	15,784
Wave-to-Wave retention [Mortality Adjusted]	––-	68.15%	79.88%	––-	84.13%	81.00%	81.65%	79.58%	85.99%	72.05%
Time 1 Retention [Mortality Adjusted]	––-	68.15%	60.74%	––-	63.26%	61.84%	58.96%	53.32%	54.24%	44.95%
Number of Booster Samples	––-	––-	1	––-	5	2	––-	––-	1	––-
Additional N (including booster, occasional opt-in partners)	––-	16	2,966	424	5,374	7,759	82	2	8,157	141
Response rate (average rate if more than 1 booster sample)	16·6%	––	92·4%	––-	9·8%	8·55%	––-	––-	9·7%	––-

Note: Response rates for Time 2, 3.5, 6, 7 and 9 are not reported as these time points did not include booster samples (these samples included participants from previous time points and occasional opt-ins). Time 3 included a non-random booster recruited from unrelated online newspaper website. Time 4 included one weighted deprivation booster and four electoral boosters (one random and the other three oversampling based on region of residence or ethnicity). Time 5 included a random electoral and Māori electoral booster. Time 8 included a random electoral booster. Around 400-450 Pacific participants were recruited informally via Pacific networks in Time 3.5.