Fig 1.
Overview of the control participant identification and recruitment process in the Ghana Breast Health Study.
Four distinct phases were involved in the identification and recruitment of study controls. As shown in the figure, existing records were used to estimate the study catchment area and the number of controls that would be needed. Household enumeration was used to generate a pool of potential controls (i.e., the sampling frame) from which women were selected and approached for study participation.
Table 1.
Areas included in the ghana breast health study household enumeration.
Fig 2.
Areas selected for the recruitment of study controls in the ghana breast health study.
Study control participants were recruited from Ghana’s Ashanti, Central, Eastern, and Greater Accra regions (highlighted in yellow, panel A). Each area is shown in greater detail in panels B, C, and D. The geographic locations of the enumeration areas used to identify the pool of potential controls are marked with pink dots. Within the Ashanti region, a large number of the enumeration areas were located within the Kumasi Metropolitan Area; a close-up view is shown in panel C.
Fig 3.
Flow chart of Ghana Breast Health Study control participation, 2013–2015, showing reasons for non-participation at right.
Eligibility was based on self-reported demographic and health information and assessed using a standardized form. Participation was defined by completion of the study’s interview-based risk factor questionnaire. The final number of 2,106 participants includes 170 who were recruited using refusal conversion.
Table 2.
Characteristics of ghana breast health study control participants, overall and according to recruitment method.
Table 3.
Ghana Breast Health Study interview-based questionnaire completion among 2,106 controls, 2013–2015.