Proxy Responses for Mass Drug Administration Coverage Surveys: The Trends and Biases When Others are Allowed to Respond
Coverage surveys for mass drug administration (MDA) rely on respondent recall and often permit proxy responses, whereby another household member is allowed to respond on behalf of an absent individual. In this secondary analysis of coverage surveys in Malawi, Burkina Faso, and Uganda, we explore the characteristics of individuals who require proxy responses and quantify the association between proxy responses and reported drug coverage. The adjusted logistic regression model found that men 11-39 years and women 11-18 years who were eligible for MDA had greater odds of requiring a proxy response compared with ineligible men and women in the same age groups. A hierarchical multivariable analysis found that proxy responses had 1.70 times the odds of reporting ingestion of MDA drugs compared with first-person responses, controlling for age and sex (95% CI: 1.17, 2.46). This finding is surprising, given that individuals absent during a coverage survey may also have been absent during the MDA, and suggests that proxy responses may be leading to an inflation of survey estimates of drug coverage. This study highlights the possibility for recall bias in proxy responses to MDA coverage; however, excluding absent individuals from coverage surveys would introduce a new bias. Further research is necessary to determine the best method for obtaining information on drug coverage when individuals are absent.
Related studies
Alternative approaches to coverage surveys (Burkina Faso)
Compare coverage evaluation methods to identify a method that is statistically rigorous and feasible for programs. This study will focus on assessing MDA coverage for lymphatic filariasis by comparing the cost, time and feasibility of 3 different methods: the EPI approach (n=1768), LQAS design (n=95) and probability sampling alternatives (n=1768).
Primary Findings and Lessons Learned
Coverage surveys are an important tool for programs to evaluate their reporting systems and to determine whether effective MDA coverage has been achieved. However, for various reasons coverage surveys are seldom implemented. Some key challenges are: perceived technical difficulty, lack of resources, and lack of standardized guidance on how to conduct coverage surveys. This protocol seeks to address the 1st and 3rd points by comparing the feasibility of three different coverage survey methods (EPI approach, LQAS, and segmentation). This study was completed in 3 districts in Burkina Faso. All 3 districts found that their survey coverage was above the WHO target threshold (65% for LF). Furthermore, in all 3 cases the survey coverage validated (or nearly validated) the reported coverage. Taken together this suggests that the Burkina Faso program is working well. The feasibility results found all 3 methods to be very similar with regards to time, cost and perceived difficulty. Because only the segmentation approach results in a probability sample, this method was recommended by the M&E Working Group and ultimately approved by the STAG. Since the approval, significant work has been underway to create guidelines for conducting coverage surveys for preventive chemotherapy. An excel tool was created to improve the usability of the tool and online learning modules are currently in the works.
Compare coverage evaluation methods to identify a method that is statistically rigorous and feasible for programs. This study will focus on assessing MDA coverage for lymphatic filariasis by comparing the cost, time and feasibility of the EPI approach (n=1768), LQAS design (n=95) and probability sampling alternatives (n=1768).
Primary Findings and Lessons Learned
Coverage surveys are an important tool for programs to evaluate their reporting systems and to determine whether effective MDA coverage has been achieved. However, for various reasons coverage surveys are seldom implemented. Some key challenges are: perceived technical difficulty, lack of resources, and lack of standardized guidance on how to conduct coverage surveys. This protocol seeks to address the 1st and 3rd points by comparing the feasibility of three different coverage survey methods (EPI approach, LQAS, and segmentation). This study was completed in 3 districts in Burkina Faso. All 3 districts found that their survey coverage was above the WHO target threshold (65% for LF). Furthermore, in all 3 cases the survey coverage validated (or nearly validated) the reported coverage. Taken together this suggests that the Burkina Faso program is working well. The feasibility results found all 3 methods to be very similar with regards to time, cost and perceived difficulty. Because only the segmentation approach results in a probability sample, this method was recommended by the M&E Working Group and ultimately approved by the STAG. Since the approval, significant work has been underway to create guidelines for conducting coverage surveys for preventive chemotherapy. An excel tool was created to improve the usability of the tool and online learning modules are currently in the works.
Alternative approaches to coverage surveys (Uganda)
To compare coverage evaluation methods to identify a method that is statistically rigorous and feasible for programs. This study will focus on assessing MDA coverage for lymphatic filariasis by comparing the cost, time and feasibility of 3 different methods: the EPI approach (n=1768), LQAS design (n=95) and probability sampling alternatives (n=1768).
Primary Findings and Lessons Learned
Coverage surveys are an important tool for programs to evaluate their reporting systems and to determine whether effective MDA coverage has been achieved. However, for various reasons coverage surveys are seldom implemented. Some key challenges are: perceived technical difficulty, lack of resources, and lack of standardized guidance on how to conduct coverage surveys. This protocol seeks to address the 1st and 3rd points by comparing the feasibility of three different coverage survey methods (EPI approach, LQAS, and segmentation). This study was completed in 3 districts in Burkina Faso. All 3 districts found that their survey coverage was above the WHO target threshold (65% for LF). Furthermore, in all 3 cases the survey coverage validated (or nearly validated) the reported coverage. Taken together this suggests that the Burkina Faso program is working well. The feasibility results found all 3 methods to be very similar with regards to time, cost and perceived difficulty. Because only the segmentation approach results in a probability sample, this method was recommended by the M&E Working Group and ultimately approved by the STAG. Since the approval, significant work has been underway to create guidelines for conducting coverage surveys for preventive chemotherapy. An excel tool was created to improve the usability of the tool and online learning modules are currently in the works.