Effects of intensive longitudinal data collection on pregnancy and contraceptive use

Abstract

We use an experiment based on the relationship dynamics and social life study of sexual behavior, pregnancy, and contraceptive use to investigate whether participation in weekly self-reports over one year result in differential effects on related behaviors and attitudes, compared to participation in a one-time follow-up interview requiring retrospective self-reporting for the prior year. We randomly assigned 200 subjects to either a control group or a journal group. All subjects were interviewed at the beginning of the study (baseline interview) and 12 months later (closeout interview). Subjects in the journal group also completed a five-minute web- or phone-based survey every week during the 12-month study period. We found no statistically significant difference in pregnancy rates across the two groups at closeout. Contrary to our expectation, the control group experienced a slightly larger increase in having ever used a contraceptive method, although this was mainly due to increases in the least effective methods, such as condoms and withdrawal. Respondents in the weekly interview group became slightly more positive toward childbearing in terms of one specific attitude measure, but not for the vast majority of measures. We conclude that intensive longitudinal data collection does not appear to have a large or consistent impact on respondents’ pregnancy, contraceptive use, or related attitudes, relative to the more standard longitudinal approach.

Keywords:

• social research
• survey research
• panel conditioning
• diaries
• intensive longitudinal data collection

Acknowledgements

The authors gratefully acknowledge the Survey Research Operations (SRO) unit at the Survey Research Center of the Institute for Social Research for their help with the data collection, particularly Vivienne Outlaw, Sharon Parker, and Meg Stephenson. The authors also gratefully acknowledge the intellectual contributions of other members of the original RDSL project team, including William Axinn, Mick Couper, and Steven Heeringa, as well as the Advisory Committee for the project: Larry Bumpass, Elizabeth Cooksey, Kathie Harris, and Linda Waite.

Notes

1. Although we are interested in the general effects of panel conditioning on contraceptive use and pregnancy, it is important to note that this design does not permit us to assess the effects of repeatedly asking about contraception and pregnancy relative to repeatedly asking about something else.

2. Respondents who indicated that they did or used something to avoid pregnancy, but who indicated that they did not use birth control pills, the patch, the ring, Depo-Provera/other injectable, or an IUD were coded ‘other.’ The most common of these methods were the ‘rhythm’ (calendar) method, condoms, and withdrawal.

Additional information

Funding

Funding. This research was supported by two grants from the National Institute of Child Health and Human Development (R01 HD050329, R01 HD050329-S1, PI Barber), a grant from the National Institute on Drug Abuse (R21 DA024186, PI Axinn), and a population center grant from the National Institute of Child Health and Human Development to the University of Michigan’s Population Studies Center (R24 HD041028).