PROJECT
Estimating the Prevalence of Induced Abortion in Mexico

In order to determine the most valid and reliable method of collecting information directly from women regarding induced abortion, Population Council researchers carried out four pilot studies in Mexico City and Chiapas State comparing the following interview techniques: face-to-face interviews, audio computer-assisted interviews (audio-CASI), self-administered questionnaires, and the random response technique (RRT). In the RRT, participants are randomly assigned to answer one of two questions: one sensitive and the other nonsensitive with a known probability (e.g., “Were you born in April?”). Based on (1) the probability of selecting the sensitive question, (2) the probability of a “yes” response to the nonsensitive question, and (3) the proportion of respondents who answer “yes” to the sensitive question, this technique allows researchers to estimate the proportion of respondents who respond affirmatively to the sensitive question.

In testing the four interview techniques to estimate abortion prevalence described above, Council researchers considered the “best” methodology to be the one that yielded the highest prevalence estimate, as they hypothesized that women were unlikely to over-report having induced an abortion. Based on the pilot studies, the RRT method yielded the highest prevalence (17 percent). The researchers then conducted a study to generate a national estimate of induced abortion using the RRT among 1,792 women aged 15–55. In this national, multistage, probabilistic sample, abortion prevalence was 16.3 percent. Three factors were associated with reporting induced abortion: having had an unwanted pregnancy, having grown up in the city, and having never given birth.

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Location

Mexico

Duration

2000–2002

Population Council researchers

Claudia Diaz, Sandra Garcia, Diana Lara

Non-Council collaborators

Carol Camlin (University of Michigan)

Jennifer Strickler (University of Vermont)

Javier Suárez (Secretaría de Desarrollo Social)

Casa de La Mujer

Instituto Nacional de Educación para Adultos

Instituto Nacional de Neurología y Neurocirugía

Donors

The William and Flora Hewlett Foundation

The David and Lucile Packard Foundation

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See Also

• Mexico
• Reducing Unsafe Abortion

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