Background: Self-harm is common in adolescents and a major public health concern. Evidence for effective interventions is lacking. An individual patient data meta-analysis has the potential to provide more reliable estimates of the effects of therapeutic interventions for self-harm than conventional meta-analyses, to explore which treatments are best suited to certain groups.
Method: A systematic review and individual patient data meta-analysis of randomised controlled trials of therapeutic interventions to reduce repeat self-harm in adolescents who had a history of self-harm and presented to clinical services. Primary outcome was repetition of self-harm. The methods employed for searches, study screening and selection, and risk of bias assessment are described, with an overview of the outputs of the searching, selection and quality assessment processes. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidance is followed.
Results: We identified a total 39 eligible studies, from 10 countries, where we sought Individual Patient Data (IPD), of which the full sample of participants were eligible in 18 studies and a partial sample of participants were eligible in 21 studies. We obtained IPD from 26 studies of 3448 eligible participants. For our primary outcome, repetition of self-harm, only 6 studies were rated as low risk of bias with 10 rated as high risk (although 2 of these were for secondary outcomes only).
Conclusions: Obtaining individual patient data for meta-analyses is possible but very time-consuming, despite clear guidance from funding bodies that researchers should share their data appropriately. More attention needs to be paid to seeking appropriate consent from study participants for (pseudo) anonymised data-sharing and institutions need to collaborate on agreeing template data-sharing agreements. Researchers and funders need to consider issues of research design more carefully. Our next step is to analyse all the data we have collected to see if it will tell us more about how we might prevent repetition of self-harm in young people.
Funding: This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number 17/117/11. A plain language summary of this research article is available on the NIHR Journals Library Website https://doi.org/10.3310/GTNT6331.
Keywords: INTERVENTIONS; IPD META-ANALYSIS; SELF-HARM; SYSTEMATIC REVIEW.
Self-harm is very common in young people and leads to an increased risk of death by suicide. Research so far has not provided clear evidence about which interventions can help to prevent self-harm repetition when young people present to services having harmed themselves. One way to understand what might help is to pool the results from lots of different clinical trials – this is known as a meta-analysis. This has already been done using the data published in research articles but has not led to clearer conclusions. In part this is because the information available in published articles is patchy and inconsistent which makes pooling the information and analysing it, difficult. A more useful approach is to ask researchers who led the clinical trials for their original ‘raw’ data and then pool and analyse all that data – this is known as an individual patient data meta-analysis. This has the added benefit that it is possible to include studies where only some of the participants are young people. We did this, and were able to identify many more study participants along with their data, compared to earlier meta-analyses. In this article, we describe how we searched for relevant research studies and the methods we used to obtain individual patient data from other researchers. We also describe our rating of the research quality of the studies we identified. We identified more studies, with many more participants in total, than in previous pooled study research. Gathering the data from other researchers was very time-consuming and not everyone was willing or able to share their data. When we rated the quality of the studies that we found, many were not of high quality. Our next step is to analyse all the data we have collected to see if it will tell us more about how we might prevent repetition of self-harm in young people.