Systematic re-review of WASH trials to assess women's engagement in intervention delivery and research activities

Water, sanitation and hygiene (WASH) services are foundational to health and well-being, yet large global gaps in access persist, disproportionately burdening women and girls who often manage household WASH tasks (e.g., water fetching, latrine cleaning, and child hygiene). These responsibilities consume time and energy, limit opportunities, and may pose health and safety risks, thereby perpetuating gender inequity. Despite acknowledgement of these unpaid burdens, WASH research and practice frequently target women to deliver interventions and to provide detailed household health and behavior data, often without assessing impacts on women’s own well-being or quantifying time burdens. The purpose of this study is to assess how women are engaged in health-related WASH research and intervention activities by re-reviewing studies from two recent Lancet systematic reviews of WASH effectiveness on diarrhoeal disease and acute respiratory infections. Specifically, the study aims to (1) identify the gender of individuals engaged in research and intervention activities; (2) determine whether time required for engagement was reported and compensated; (3) assess whether additional impacts specific to women were evaluated; and (4) characterize intervention engagement using the WHO Gender Responsiveness Assessment Scale (GRAS).

Prior systematic reviews show that WASH services significantly reduce risks of diarrhoea and acute respiratory infections in low- and middle-income settings, with substantial global disease burden attributable to unsafe WASH. However, evidence gaps persist regarding broader health outcomes for women and girls (e.g., bodily injury, violence, stress). Literature documents that women and girls often bear household WASH responsibilities due to gender norms, and WASH programs commonly leverage these roles by targeting women for tasks like household water treatment, child faeces management, and hygiene promotion, typically justified by child health benefits. Reviews of point-of-use chlorination adoption highlight that interventions frequently target women and note time burden as a barrier, though seldom quantified. Women are also routinely relied upon in research to report family behaviors and health outcomes. Potential co-benefits of higher service-level WASH (e.g., piped water or passive chlorination) for women—time and labor savings and reduced caregiving burdens—are rarely assessed. These gaps motivate a comprehensive appraisal of women’s engagement and gender-responsiveness in WASH interventions and evaluations.

Design: Systematic re-review of studies included in two recent Lancet systematic reviews evaluating effectiveness of water, sanitation and/or handwashing with soap interventions on diarrhoeal disease and acute respiratory infections. The protocol was registered in PROSPERO (CRD42022346360) and reporting followed PRISMA guidelines. Eligibility: All papers from the two source reviews published in English or Spanish were eligible; studies in other languages were excluded. Sample: Of 150 studies from the source reviews, 14 duplicates and 3 non-eligible language papers were removed, yielding 133 studies. One intervention appeared in two studies (one each in the diarrhoea and ARI reviews) and was retained as two records due to potentially different engagement reporting. Data extraction: Two reviewers independently extracted data using a standardized template (available on Figshare). After piloting on five papers to harmonize understanding, dual extractions were reconciled; discrepancies were resolved by re-extraction or discussion with a third reviewer as needed. Extracted variables included: whether research and intervention activities required individual-level participation; who was engaged/targeted (women, men, women or men, girls, boys, children, other specified or unspecified); who reported the focal outcome; whether time required for engagement was reported; whether compensation was provided; whether additional outcomes specific to women, men, girls, or boys were assessed; and whether intervention communications referenced gender norms (e.g., shame, honor, traditional values such as ‘good mothers’). Gender responsiveness assessment: Interventions requiring individual-level participation were classified using an adapted WHO Gender Responsiveness Assessment Scale (GRAS), with categories: gender unequal, gender unaware, gender sensitive, gender specific, and gender transformative. Following WHO and Pederson et al., categories were interpreted along exploit–accommodate–transform axes; the term ‘gender blind’ was replaced by ‘gender unaware’. Two reviewers independently categorized intervention components (water, sanitation, hygiene) and overall interventions; disagreements were resolved with a third reviewer. Non-WASH components (e.g., nutrition) were not assessed. Analysis: Descriptive statistics were generated in R (v4.0.5). GRAS classifications were summarized overall and by WASH component and organized by exposure scenarios adapted from prior work aligned with WHO/UNICEF Joint Monitoring Programme service ladders (water, sanitation, hygiene) to examine gender responsiveness across service levels.

• Corpus: 133 studies included; most interventions focused on water (64; 48.1%) or hygiene (46; 34.6%). Majority set in rural areas (80; 60.2%), mainly Asia (51; 38.3%) and Africa (43; 32.3%). Only 8 (6.0%) studies reported sex-disaggregated primary outcomes. Research engagement: - 132/133 (99.2%) studies included at least one research activity requiring individual-level participation; 92 (69.7%) engaged multiple groups; 89 (67.4%) did not clearly specify at least one engaged group. - Among specified participants, women were most frequently engaged: 91/132 (68.9%); women were the only group engaged in 14 (10.6%). Children were engaged in 47 (35.6%); men in 2 (1.5%). - Common research activities for women: surveys (63; 47.7%), diarrhoea recall (53; 40.2%), behavior/practice recall (18; 13.6%), observation (18; 13.6%). Children were most engaged for biological specimens (stool/rectal swabs: 15; 11.4%; sera: 9; 6.8%). - The focal outcome reporter (n=131): women (mothers) in 83 (63.4%); parents as a unit in 8 (6.1%); school/daycare staff in 7 (5.3%); children in 3 (2.2%); unspecified 28 (21.4%). - Additional outcomes reported in 111 (83.5%) studies: children-specific in 60 (54.1%); women-specific in 16 (14.4%)—3 on women’s well-being (e.g., childcare hours saved, sanitation satisfaction, water fetching time) and the remainder programmatic compliance; men-specific in 4 (3.6%). - Time burden for research activities reported in 1 (0.8%) study; compensation reported in 5 (3.8%). Intervention engagement: - 120/133 (90.2%) studies included at least one intervention activity requiring individual-level participation; 48 (40.0%) targeted multiple groups; 76 (63.3%) did not specify at least one targeted group. - Among those specifying targets, women were most targeted: 49/120 (40.8%), including 21 (17.5%) studies targeting only women. Children were targeted in 20 (16.7%), including 2 (1.7%) only children; men were targeted in 2 (1.7%). - By activity domain (N=120 studies): water-related activities targeted women in 46 (38.3%); sanitation-related in 15 (12.5%); hygiene-related in 35 (29.2%); health promotion in 29 (24.2%). - References to gender norms/shame/honor in intervention communications appeared in 10 (8.3%) studies. - Time burden for intervention activities reported in 3 (2.5%); compensation provided in 13 (10.8%). Gender responsiveness (GRAS): - Overall, all interventions requiring individual-level participation were classified as gender unequal (44; 36.7%) or gender unaware (76; 63.3%); none were gender sensitive/specific/transformative. - Water components (n=77; 68 required individual involvement): gender unequal 24 (35.3%); gender unaware 44 (64.7%). Point-of-use water treatment (n=57): gender unequal 22 (38.6%); gender unaware 35 (61.4%). One improved, on-premises continuous supply intervention did not require individual participation (not GRAS-assessed). - Sanitation components (n=18; 13 required individual involvement): gender unequal 3 (23.1%); gender unaware 10 (76.9%). Four with sewer connections did not require individual participation (not GRAS-assessed). - Hygiene components (n=57; all required individual involvement): gender unequal 23 (40.4%); gender unaware 34 (59.6%). Handwashing promotion with soap provision (n=34): gender unequal 10 (29.4%); gender unaware 24 (70.6%). Without soap provision (n=23): gender unequal 13 (56.5%); gender unaware 10 (43.5%). - In one intervention reported in two studies, differing specificity about targeted engagement yielded different GRAS classifications (gender unaware vs gender unequal). Overall implication: Women are critical to both research and intervention delivery in WASH trials, yet their roles are largely instrumentalized; time burdens and compensation are rarely reported; interventions predominantly exploit gender norms rather than address inequalities.

The re-review shows that many WASH interventions and evaluations rely heavily on women as implementers and key data providers yet seldom acknowledge or compensate their time, nor assess impacts on their own well-being. Classifications under GRAS reveal that interventions are overwhelmingly gender unequal or gender unaware—approaches considered exploitative and not recommended. This exploitation reinforces and potentially deepens existing gender norms that deem WASH-related labor as women’s work of low value, thereby reproducing inequalities. Furthermore, program costs are understated when women’s unpaid labor is not accounted for, which can skew perceptions of cost-effectiveness and shape donor and policy preferences for household-level, behavior-change-focused approaches that extract ‘free’ labor. Lower service-level interventions—often those emphasizing behavior change—are both more likely to be exploitative and generally less effective, particularly in contexts where enabling environments are absent. Interventions that provide higher service levels (e.g., on-premise improved water, sewered sanitation) can reduce household labor demands, but gender equity is not guaranteed without intentional design. The study calls for pre-implementation gender-responsiveness assessments (e.g., GRAS) to redesign or avoid exploitative approaches, transparent reporting on who is engaged, rigorous measurement of time and opportunity costs, appropriate participant compensation, and adoption of SAGER guidelines to close sex/gender data gaps. An intersectional perspective is also needed to understand how gender intersects with other identities to shape WASH-related inequities. Elevating gender equity as an explicit objective alongside health outcomes is essential for ethical and effective WASH programming and research.

This re-review demonstrates that women’s engagement in WASH trials is pervasive but predominantly instrumentalized, with interventions classified as gender unequal or gender unaware and limited attention to women’s own outcomes, time burdens, or compensation. The main contributions are (1) quantifying who is engaged in research and intervention activities across a large body of WASH trials, (2) documenting sparse reporting of time burdens and compensation, (3) showing near-absence of sex-disaggregated outcomes and women-specific well-being measures, and (4) applying the WHO GRAS to reveal widespread exploitative engagement, especially at lower service levels. Future directions include: integrating gender-responsiveness assessments during program design; prioritizing higher service-level WASH that reduces unpaid household labor; systematically measuring and compensating participant time; adopting SAGER-aligned reporting; and using intersectional frameworks to evaluate how WASH benefits and burdens are distributed. Funding and publication of exploitative interventions should be reconsidered.

Findings reflect only what was reported in included papers and may underestimate engagement, time burden, or compensation where reporting was unclear or absent. The sample was limited to studies included in two specific systematic reviews and to English or Spanish publications, potentially restricting generalizability. Subjectivity in GRAS categorization was mitigated through independent dual review and adjudication but cannot be fully eliminated. Non-WASH components of multi-component interventions were not assessed.