Inverse probability weights for continuing in the study in wave 4 were calculated for all participants conditioned on their participation in wave 3. We created a binary variable for dropping out, D4, in wave 4. If the participant dropped out in wave 4 but participated in wave 3, then D4 = 1, and if they didn't dropout then D4 = 0.
For the respondents who had stopped drinking at wave 0 and participated in wave 5, there was a modest reduction in the level of poor self-rated health at wave 5.
Another finding was that those who stopped drinking by wave 0 but participated in wave 5 were more likely to report improved health ten years later than those who never drank or drank occasionally.
Despite the response rate in wave 1 being quite low, more than 75% of those who participated in wave 1 also participated in wave 3.
In this study we allowed survivors who participated at wave 1 but not at wave 2 to re-enter the study at wave 3.
Of the 10,090 families that participated at Wave 1, 9,070 (89.9%) participated at Wave 2 and 8,718 (86.4%) participated at Wave 3. Data from both cohorts were used for this study.
First, we limited to females who participated in Wave IV, as that was the Wave when all respondents had completed their teenage years and had complete teen pregnancy data.
For this paper, we used data from the pairs who participated at wave 1, were aged 11 18 years (comprising 99% of wave 1 pairs) and who participated in a subsequent wave.
Follow-up interviews for waves 3 (2001–02; response rate 77.4%) and 4 (2008–09; response rate 80.3%) were conducted with individuals who had participated in wave 1, leaving 12,288 participants who had sampling weight information.
Of the final 76 MZ twin pairs selected for this study, 18 pairs participated in wave 2002 only, 28 pairs participated in two waves, 4 pairs in three, 8 pairs in four, 13 pairs in five, and 4 pairs in all six waves.
