Under-reporting of gravidity in a rural Malawian population.

BACKGROUND: Mis-reporting of data by study participants in a questionnaire-based study is an important source of bias in studies.
OBJECTIVE: To determine the prevalence and factors influencing mis-reporting of gravidity among rural women in Malawi.
MATERIALS AND METHODS: Data from cross sectional study conducted in 2004 were analysed using logistic regression analysis and the logit modeling.
RESULTS: 7118 women were in the reproductive age group, 2387(33.5%) had ever attended school, 4556 (64.0%) had never and results for 175 (2.5%) were missing. Of those who attended school, 94.9% (2297) had attained a maximum primary level, 5.04% (122) secondary level and 0.08% (2) tertiary level. 81.6% of the women were aged between 12 and 36 years of age, mean was 26.1 years (SD 10.05 years). The remaining 18.4% were aged between 37 and 49 years of age. The mean number of pregnancies attained was 4.0 (SD 3.4), live births was 3.0 (SD 3.2), mean number of stillbirths was almost zero (SD 0.9) and the mean number of children alive was 2.0 (SD 2.3). The prevalence of mis-reporting of gravidity was 7.9%. Factors influencing the risk of under-reporting gravidity were: previous experience of a still-birth, young age, not being married and having ever attended some level of education.
CONCLUSIONS: We suggest that women who perceived that the community expected them, or they expected themselves to have fewer or no pregnancy at all, censured themselves in reporting low number of pregancies. Researchers using questionnaires should keep in mind possibility of mis-reporting of number of pregnancies among women as this may introduce error in research results. Incorporating multiple questions asking the same thing but in a different way has potential to identify biases as these other questions serve as consistency checks.