Increasing participation in a vector control campaign: a cluster randomised controlled evaluation of behavioural economic interventions in Peru

Abstract

ObjectiveTo assess the efficacy of strategies informed by behavioural economics for increasing participation in a vector control campaign, compared with current practice.DesignPragmatic cluster randomised controlled trial.SettingArequipa, Peru.Participants4922 households.InterventionsHouseholds were randomised to one of four arms: advanced planning, leader recruitment, contingent group lotteries, or control.Main outcome measuresParticipation (allowing the house to be sprayed with insecticide) during the vector control campaign.ResultsIn intent-to-treat analyses, none of the interventions increased participation compared with control (advanced planning adjusted OR (aOR) 1.07 (95% CI 0.87 to 1.32); leader recruitment aOR 0.95 (95% CI 0.78 to 1.15); group lotteries aOR 1.12 (95% CI 0.89 to 1.39)). The interventions did not improve the efficiency of the campaign (additional minutes needed to spray house from generalised estimating equation regressions: advanced planning 1.08 (95% CI −1.02 to 3.17); leader recruitment 3.91 (95% CI 1.85 to 5.97); group lotteries 3.51 (95% CI 1.38 to 5.64)) nor did it increase the odds that houses would be sprayed in an earlier versus a later stage of the campaign cycle (advanced planning aOR 0.94 (95% CI 0.76 to 1.25); leader recruitment aOR 0.68 (95% CI 0.55 to 0.83); group lotteries aOR 1.19 (95% CI 0.96 to 1.47)). A post hoc analysis suggested that advanced planning increased odds of participation compared with control among households who had declined to participate previously (aOR 2.50 (95% CI 1.41 to 4.43)).ConclusionsAchieving high levels of household participation is crucial for many disease prevention efforts. Our trial was not successful in improving participation compared with the existing campaign. The trial highlights persistent challenges to field experiments as well as lessons about the intervention design process, particularly understanding barriers to participation through a behavioural lens.Trial registration numberAmerican Economic Association AEARCTR-0000620.

A behavioral design approach to improving a Chagas disease vector control campaign in Peru

“…The results from this trial are reported in detail elsewhere [41]. Briefly, Cycle 2 participation was high (over 80%) in the study area, with little difference across study arms (see Fig.…”

“…Brigade chiefs could not plan that far ahead of time due to water shortages, health sector strikes, holidays, and a canine rabies outbreak.Households scheduled in advance were often not home for spray appointment.Advance scheduling was revised to 7–10 days ahead of spraying.Spray brigade schedule was intentionally “overbooked” to account for no-shows.Households are not able to plan for spraying when scheduled only 1 day prior.Planning prompts can help follow through on desired behavior. [39–41]Offer planning prompts as well as email, text message, phone call or visit reminders to advance scheduled households.Few households chose email or text message remindersOnly call or visit reminders were offered.Those working during the day cannot participate.Provide more flexible scheduling options to households (evenings and weekends, more choice of spraying time).Evening hours were not feasible for the spray brigade, although frequently requested by households. Weekend spraying was used for “recuperation,” or to catch up, but could not be scheduled in advance.Households scheduling in advance could choose preferred appointment times during the regular spray day but not weekend or evening hours.Sprayer arrival time is unpredictable.Spray households according to pre-arranged schedule (rather than proceeding house-by-house down a block).If households scheduled in advance were not at home for spray appointment, sprayers could not “make up” the missed appointments by spraying nearby households, as these were also scheduled in advance.We staffed up extra sprayers to fill in when regular spray brigades could not accommodate the pre-arranged schedule.…”

“…Of course, we have to note that the results from our cluster randomized trial of almost 5000 households showed no significant increases in participation for our behaviorally-designed interventions compared to the control campaign [41]. We discuss possible reasons for this finding elsewhere [41], but are reluctant to infer from this one trial that the behavioral design approach is ineffective. The pragmatic, real-world setting of our study made the behavioral design approach challenging, productive, and focused.…”

Nudge strategies for behavior-based prevention and control of neglected tropical diseases: a scoping review and ethical assessment

“…The included studies did not specify a disease which the intervention was focused on specifically, apart from two studies targeting Chagas disease [43] and trachoma [66]. The studies targeted specific behaviors rather than diseases and merely described possible health effects of these behaviors, mostly a decrease of infectious pathogens causing a host of illnesses (e.g., diarrhea, pneumonia).…”

“…Finally, decision information was the least used category with 5 nudges using "translate information" through simplification and message reframing [38,52,58,60], 3 nudges using "provide social reference point" referring to role-models [39,43,48,49], and 2 nudges implementing "make information visible" through visualization of the future and providing visual feedback [44,52]. The results of each of the eight ethical criteria described in Table 3 are presented below one by one, and the findings are visualized in Figure 4 targeted behaviors during specified moments such as water disinfection, or involving a certain group (e.g.…”