By applying the genetic search, the most important questionnaire statements are determined and a support vector machine (SVM) classifier is designed for categorizing the questionnaire data into the healthy, nodular and diffuse classes.
Knowledge of stroke/TIA risk factors is defined as the number of correctly identified factors in the questionnaire, categorized into 3 groups: good, moderate or poor knowledge.
Weight changes during the participant's adult lives were obtained by self-report questionnaire, categorized as weight stayed stable (within 10 lb), steady gain in weight, lost weight as an adult and kept it off, and weight has gone up and down again by more than 10 lb.
Mean daily intake of water, wine, beer or cider, and sweet beverages was categorized in the questionnaire into six mutually exclusive levels: none, <0.5, 0.5 to 1, 1 to 1.5, 1.5 to 2.0, and >2 L. In the present analyses, the levels were grouped into three classes: <0.5, 0.5 to 1, and >1 L. Other clinical and biological measurements are presented in the Supplementary Methods.
Study design: Cross-sectional study using a pre-categorized questionnaire which was compiled by the research group of the University of Tartu and the research provider EMOR.
Results: Among 41 (25%) questionnaires categorized independently by 2 investigators, strength of agreement in categorizing 68 pain problems was substantial (κ=.68).
The questionnaire was categorized into sections.
Six women (2%) who had quit smoking in early pregnancy (questionnaire) were categorized as nonsmokers in the interview.
We assessed maternal smoking during pregnancy by questionnaire and categorized responses into former smoker, never smoker, and smoked during pregnancy.
Smoking was assessed by questionnaire and categorized as current smoker, past smoker or never smoked [ 32].
Surveys returned before the mailing of the second questionnaire were categorized "first mailing respondents".
