Main findings of the review

We aimed to provide pooled prevalence estimates of different types of suicidal behaviour among students living in Muslim-majority countries. We found that about one in five students (high school and university) had experienced suicidal ideation at some point in their lifetime. One in eight students reported experiencing suicidal ideation in the year before assessment, whereas one in 16 reported experiencing it at the time of assessment; these prevalence rates were significantly higher among high school students compared with university students. Pooled prevalence rates of lifetime suicide plans and suicide attempts were similar; about one in 16 had experienced these phenomena. One in 20 students reported making an attempt to end their life in the year before assessment; once again, the prevalence was significantly higher among elementary school students compared with university students.

One in six students reported NSSI behaviours during their lifetime, with about one in ten reporting such phenomena in the year before the assessment. Interestingly, the prevalence of NSSI behaviours was significantly higher among university students compared with school (high and elementary) students. Overall, few studies provided data for comparison of the regional prevalence of suicidal behaviours. Prevalence of lifetime suicidal ideation was highest in South-East Asia, but the corresponding 12-month prevalence rates were highest among students in Eastern Mediterranean countries; for other suicidal behaviours, the number of studies was too few to make meaningful interpretations. These findings were, largely, robust across sensitivity analyses excluding low-quality studies.

Implications of findings

Traditionally, as suicide is proscribed in Islam, suicide rates in Muslim countries have been thought to be low. However, the data have been inconsistent,^{Reference Arafat, Marthoenis, Khan and Rezaeian16} and there has been no systematic collection of national suicide data and reporting in many Muslim nations.^{Reference Shah and Chandia102} As pointed out by Pritchard et al in their population-based study comparing differences in patterns of suicide, undetermined and accidental deaths between Islamic and Western nations, underreporting of suicides was common, with greater underreporting noted in more orthodox Islamic nations such as Middle Eastern and North African nations compared with less orthodox countries.^{Reference Pritchard, Iqbal and Dray103} Interestingly, underreporting of suicide was also noted in Western nations and, given the stronger cultural taboos against suicide in Muslim nations, the authors argued that this may explain the relationship between level of religiosity and underreporting of suicide.

Given this background, our findings provide the first meta-analytic evidence for suicidal behaviour among students in Muslim countries. In fact, our pooled prevalence estimates for all subtypes of suicidal phenomena were higher than what had been reported in the general population in prior national and cross-national meta-analytic reviews.^{Reference Nock, Borges, Bromet, Alonso, Angermeyer and Beautrais104,Reference Kessler, Borges and Walters105} They were also higher than figures noted in prior national and cross-national reviews on college students, particularly for suicide attempts.^{Reference Mortier, Cuijpers, Kiekens, Auerbach, Demyttenaere and Green106,Reference Yang, Zhang, Sun, Sun and Ye107} These findings suggest the need for instituting robust suicide surveillance and data-gathering mechanisms to design effective suicide prevention programmes aimed at high school and university students in Muslim-majority countries. They also suggest the need for these issues to be high on the research and policy agenda. As our results show, authorities in Muslim nations should regard suicide as a public health issue, and not minimise its extent or severity. In many Islamic nations, suicide attempt is a punishable offence; in this context, decriminalisation of attempted suicide would be a welcome step to encourage suicide reporting, and more importantly, reduce stigma and improve help-seeking behaviour.^{Reference Mishara and Weisstub19} Finally, considering suicide as an outcome of social and mental health issues in Muslim nations, best practices for assessing suicide and suicide risk in a sensitive, non-judgemental manner that neither decreases the patient's self-esteem nor challenges their religious beliefs, would enhance suicide reporting and improve help-seeking behaviour. This may enhance data-gathering efforts.

The prevalence of suicidal ideation noted was higher than what was reported in three other multi-country studies, all of whom reported prevalence rates of 12%–17%.^{Reference Uddin, Burton, Maple, Khan and Khan108–Reference McKinnon, Gariépy, Sentenac and Elgar110} The prevalence figures for suicide plan were higher than those reported by McKinnon et al (5.8%-8.3%),^{Reference McKinnon, Gariépy, Sentenac and Elgar110} but lower than those reported by Uddin et al (17%).^{Reference Uddin, Burton, Maple, Khan and Khan108} With regard to lifetime suicide attempts, our pooled estimates were lower than a large, cross-national analysis from 53 LMICs (11%).^{Reference Abio, Owusu, Posti, Bärnighausen, Shaikh and Shankar111} Likewise, the past year attempt rates were also lower than two prior reports, also from LMICs.^{Reference Mortier, Cuijpers, Kiekens, Auerbach, Demyttenaere and Green106,Reference Uddin, Burton, Maple, Khan and Khan108} However, as mentioned before, the figures were higher than those reported in multinational analysis not restricted to low-resource settings.^{Reference Mortier, Cuijpers, Kiekens, Auerbach, Demyttenaere and Green106} These variations may reflect, in part, differences in the meaning, context and attitudes toward suicide in various cultural, religious and economic settings. The increased figures of suicidal ideation and suicide attempt noted may reflect pressures of rapid socioeconomic transition in Muslim nations with attendant intergenerational conflicts, which when coupled with academic stress, can contribute to suicidal behaviours.^{Reference Rezaeian112}

Interestingly, although our pooled prevalence estimates for lifetime and past year suicidal ideation and lifetime suicide plans were comparable with prior cross-national reviews on college and university students, differences in prevalence rates were more pronounced for past year suicide plans and both lifetime and past year suicide attempt.^{Reference Mortier, Cuijpers, Kiekens, Auerbach, Demyttenaere and Green106,Reference Crispim, Santos, Frazão, Frazão, Albuquerque and Perrelli113} This raises the intriguing possibility that students in Muslim countries may have higher rates of transition from suicidal ideas or plans to a suicide attempt, compared with their counterparts in other countries. This must be systematically examined in future research, along with risk factors for such transitions, as it has obvious implications for suicide prevention. Prior research has shown that the majority of transitions from ideation to attempt occur in the first year following onset of suicidal ideation. Additional risk factors identified were younger age, female gender and presence of psychiatric morbidity.^{Reference Nock, Borges, Bromet, Alonso, Angermeyer and Beautrais104} These relevant cultural factors need to be investigated in this context, to identify subgroups of students at a higher risk of suicidal behaviour transition.

Prevalence of suicidal behaviours was higher among high school students compared with university students. Indeed, the figures were higher than that found in prior analyses on high school students and adolescents.^{Reference Lowry, Crosby, Brener and Kann114,Reference Nock, Green, Hwang, McLaughlin, Sampson and Zaslavsky115} Prior observations from Turkey, showing a high proportion of university students contemplating suicide compared with their counterparts from Western countries, are consistent with what we have found.^{Reference Zeyrek, Gençöz, Bergman and Lester116} There is a need to explore the role of commonly implicated risk factors for suicide and suicidal behaviour in this group, such as mental health issues, academic stress and exposure to violence in the school and community.^{Reference Bilsen117–Reference Lubell and Vetter119} At the same time, there is a need to assess and strengthen protective factors that may reduce the risk of suicide. Some of the evidence-based protective factors in this group are increasing levels of parental supervision, and better parent–child and school–child connectedness.^{Reference Borowsky, Ireland and Resnick120} Whether enrolment in a university confers additional risk over and above that experienced by peers in Muslim countries who do not attend university may be investigated, to know whether a causal relationship exists between university attendance and suicidal behaviours.

Rates of suicidal ideation were higher in the South-East Asian and Eastern Mediterranean regions. For other suicide constructs, few studies provided data for a meaningful interpretation of regional variations. Prior analysis of age-standardised suicide rates in Muslim-majority nations has also shown considerable regional variations.^{Reference Arafat, Marthoenis, Khan and Rezaeian16,Reference Lew, Lester, Kõlves, Yip, Chen and Chen121} Suicide is a complex, multidimensional behaviour anchored in unique sociocultural contexts. Existing studies identified that the suicide rate is higher in African Muslim countries than in Asia and Europe.^{Reference Arafat, Marthoenis, Khan and Rezaeian16,Reference Lew, Lester, Kõlves, Yip, Chen and Chen121} Further studies are warranted to explore this variation.

From a preventive standpoint, our findings highlight the importance of understanding drivers of suicidal behaviour among students living in Muslim countries. Specifically, there is a need to understand factors that may drive progression from suicidal ideation to behaviours in this group, to inform actionable strategies for the prediction and prevention of suicidal behaviour. Existing adolescent suicide prevention programmes can be divided into two types: strategies for early recognition and referral of at-risk individuals through comprehensive, periodic, school-based screening programmes; and strategies aimed at addressing risk or protective factors in this group.¹²² Given the high burden of suicide among high school students, we also recommend incorporation of life skills training, also recommended by the WHO, and stress management materials into the school curriculum.¹²³ A recent review of suicide prevention strategies among university students found that gatekeeper training of peer counsellors, combining education with skills training, is effective in improving knowledge about suicide and boosting self-efficacy in suicide prevention.^{Reference Cecchin, Murta, de Macedo and Moore124}

Methodological considerations

Paradoxically, the 12-month prevalence of suicide plans was higher than the lifetime prevalence. A possible reason for this may be recall bias, noted in other contexts.^{Reference Lim, Tam, Lu, Ho, Zhang and Ho125} Specifically, participants may underreport past suicide plans or behaviours, and thus, studies assessing lifetime suicide phenomena may report lower prevalence than those assessing recent phenomena. This may be particularly relevant for suicide plans, which are not as well-defined as suicidal ideation/attempt. It might be complicated by how the terminologies for suicidal thoughts and behaviours used by the researchers were understood by the students living in countries where suicide is socially proscribed and a criminal offence.

A striking finding was that most included studies were of low to moderate quality, with most studies falling short on the domains of sample representativeness. This would influence the grade of evidence and the strength of recommendations. Different studies used different instruments to assess suicidal behaviour. Further, more than half of the included studies came from the Eastern Mediterranean region. There was also a disproportionate contribution from a few countries; only one study was available from Africa. This imbalance in the geographical distribution of studies suggests the need for expanded and high-quality research on student suicide across Muslim-majority nations.

Most of the studies used self-report questionnaires, which might be prone to recall bias and social desirability bias, both of which may lead to systematic underreporting. This issue may have particular significance when assessing issues such as suicidal behaviour and mental health, both of which are issues surrounded by stigma. As such, it is possible that participants may have modified their responses to report desirable attributes that better suit their situation. Further, the use of single-item measures or selected items from a larger measure to assess suicidal behaviours, used in some studies in the present review, is prone to misclassification error and may have influenced the reported rates of suicidal behavior.^{Reference Millner, Lee and Nock126}

Strengths and limitations

Suicide is under-researched in Muslim-majority countries. It is the first systematic review and meta-analysis revealing higher rates of suicidal behaviour among the students of Muslim-majority countries. These findings would encourage practicing psychiatrists to assess suicidal behaviour when treating mental health issues among students. There were many limitations to the present meta-analysis. First, the quality of the majority of studies used in this meta-analysis was low or moderate, and only 10% of the studies were of high quality. This may have biased the cross-national comparisons. Second, there was a disproportionate research output from several nations, and therefore, the results may not be generalisable to other Muslim-majority nations from which there was little to no data. Third, an overwhelming majority of included studies were conducted in specific urban settings, and thus, the results may not be generalisable to other settings and regions in the countries. Fourth, the instruments measuring the suicidal behaviour varied widely. Data from included studies were mostly based on retrospective self-report of suicidal thoughts and behaviours, which may be subject to recall bias or deliberate underreporting. The latter may be particularly relevant in a study of this nature because of the religious sanctions against suicide in Islam and its criminal status in some Muslim nations.^{Reference Mishara and Weisstub19} Fifth, the age of the participants varied widely in this meta-analysis, which limits the power of subgroup analyses for specific developmental time periods. We have not assessed sociodemographic or clinical risk factors for suicide, and this affects our ability to understand the broad basis of suicidal behaviour in the studied settings. Sixth, we have not studied the rates of transition from ideation to planning to attempt, as this information was not available in studies. This is an important focus for future research because of its obvious implications for suicide prevention. Finally, many subgroup analyses lacked statistical power because there were a limited number of studies that provided the necessary data, which led to a greater probability of false negative results.^{Reference Cuijpers, Griffin and Furukawa127}

The study revealed notably high rates of suicidal behaviours among students living in Muslim-majority countries. The pooled lifetime prevalence of suicidal ideation, plan and attempt among students was 21.9%, 6.4% and 6.6%, respectively. However, the quality of studies, differences in regional and cultural factors, stages of studentship and methods of measurement should be considered when generalising the study results.