A community-based cluster randomised trial of safe storage to reduce pesticide self-poisoning in rural Sri Lanka: study protocol

Abstract

BackgroundThe WHO recognises pesticide poisoning to be the single most important means of suicide globally. Pesticide self-poisoning is a major public health and clinical problem in rural Asia, where it has led to case fatality ratios 20-30 times higher than self-poisoning in the developed world. One approach to reducing access to pesticides is for households to store pesticides in lockable "safe-storage" containers. However, before this approach can be promoted, evidence is required on its effectiveness and safety.Methods/DesignA community-based cluster randomised controlled trial has been set up in 44,000 households in the North Central Province, Sri Lanka. A census is being performed, collecting baseline demographic data, socio-economic status, pesticide usage, self-harm and alcohol. Participating villages are then randomised and eligible households in the intervention arm given a lockable safe storage container for agrochemicals.The primary outcome will be incidence of pesticide self-poisoning over three years amongst individuals aged 14 years and over. 217,944 person years of follow-up are required in each arm to detect a 33% reduction in pesticide self-poisoning with 80% power at the 5% significance level. Secondary outcomes will include the incidence of all pesticide poisoning and total self-harm.DiscussionThis paper describes a large effectiveness study of a community intervention to reduce the burden of intentional poisoning in rural Sri Lanka. The study builds on a strong partnership between provincial health services, local and international researchers, and local communities. We discuss issues in relation to randomisation and contamination, engaging control villages, the intervention, and strategies to improve adherence.Trial RegistritationThe trial is registered on ClinicalTrials.gov ref: NCT1146496 (http://clinicaltrialsfeeds.org/clinical-trials/show/NCT01146496).

Overdose of oral contraceptive pills as a means of intentional self-poisoning amongst young women in Sri Lanka: considerations for family planning

“…The first case series was a cross-sectional survey of self-harm cases (unpublished data) from 48 primary hospitals located within the NCP for the period 1 January to 31 December 2011. The second case series was harvested from a surveillance study of self-harm cases registered at primary ( n =10) and referral ( n =2) hospitals located mainly within the Mahaweli H region of the NCP for the period January 2012 to June 2014 8. In both studies, wards covered for data collection included medical wards (male and female) and paediatric wards (age ≤12 years).…”

Risk factors associated with purchasing pesticide from shops for self-poisoning: a protocol for a population-based case–control study

“…Cases and Control group A will be selected from the ongoing Safe Storage prospective cohort26 identified through the rural hospital network. This consists of 11 peripheral hospitals and 2 secondary/tertiary care hospitals.…”

“…This consists of 11 peripheral hospitals and 2 secondary/tertiary care hospitals. These hospitals care for >99% of self-harm admissions (unpublished data from Safe Storage study26) from the study area.…”

“…Fatal self-poisoned patients will also be excluded from the study as data obtained from next of kin are likely to be inaccurate or missing important study variables. Participants who are not confident of being interviewed in Sinhala language will be excluded from the study (based on unpublished data from the Safe Storage study26 we expect that <1% of the patients cannot be interviewed in Sinhala).…”

“…This consists of 11 peripheral hospitals and 2 secondary/tertiary care hospitals. These hospitals care for >99% of self-harm admissions (unpublished data from Safe Storage study 26 ) from the study area. Control group B participants are those who bought pesticides at the same shop within 7 days of the relevant case purchase without using these for self-harm.…”