This protocol describes a systematic review that will synthesize epidemiological evidence on multilevel risk factors and methods of non-suicidal self-injury (NSSI) and suicide attempts among American Indian and Alaska Native (AI/AN) adolescents and young adults aged 10–25 years in the United States. The review will also examine indicators of clinical severity or lethality, such as emergency department (ED) presentation, hospitalization, intensive care admission, and case fatality. The protocol follows PRISMA-P 2015 guidance, the completed review will be reported using PRISMA 2020, and the project is prospectively registered on the Open Science Framework (OSF ID: rjf2u).
Suicide ranks among the leading causes of premature mortality worldwide and is a major public health concern for adolescents and young adults. In the United States, non-Hispanic AI/AN populations experience the highest suicide rates of any racial or ethnic group. Between 2015 and 2020, suicide rates among AI/AN individuals rose by nearly 20%, substantially outpacing the overall U.S. population.
AI/AN youth aged 10–24 years face particularly high burden: suicide is the second leading cause of death in this age group and age-adjusted rates for AI/AN individuals aged 15–24 years substantially exceed national averages. Non-fatal suicidal behavior is far more common than suicide death; identification and study of suicide attempts is therefore critical because prior attempt is a strong predictor of subsequent suicide death.
The authors situate suicidal behavior within broader structural, historical, and sociocultural determinants. AI/AN communities have experienced colonization, forced relocation, land dispossession, cultural suppression, and intergenerational trauma. Structural factors—poverty, under-resourced healthcare systems, rural isolation, and exposure to violence—contribute to elevated vulnerability. The protocol also notes emerging evidence that environmental exposures (for example, higher temperatures and extreme weather) may be associated with suicidality, although much of that evidence pertains to suicide mortality rather than non-fatal outcomes.
Understanding not only risk factors but also the methods used in attempts is essential because method choice strongly influences medical severity and fatality. Patterns of method use are shaped by access to means, geographic context, and sociocultural norms. The review will therefore examine method distribution and method-specific indicators of clinical severity.
This systematic review protocol is structured using a Population–Exposure–Outcome–Study design (PEOS) framework and adheres to PRISMA-P 2015 recommendations. The authors commit to documenting any protocol amendments in the OSF registry and to reporting the completed review according to PRISMA 2020.
The protocol was prepared following PRISMA-P 2015. The completed review will follow the PRISMA 2020 statement. The systematic review protocol has been prospectively registered with the Open Science Framework (Registration ID: rjf2u). Any protocol amendments will be dated, described, and justified in the OSF record.
Eligibility is defined using the PEOS framework. The review will include observational and epidemiological studies that report on non-fatal self-harm, NSSI, or suicide attempts among AI/AN adolescents and young adults in the United States. Studies that do not disaggregate AI/AN data or that focus on Indigenous populations outside the United States without separate AI/AN reporting will be excluded. For mixed-race samples, inclusion requires that AI/AN participants be reported separately or constitute a reportable subgroup.
The target population is AI/AN adolescents and young adults aged 10–25 years who reside in the United States. Studies with broader age ranges may be included if results for the 10–25 age group are reported separately or if the sample mean age falls within the specified range.
The review will consider a broad set of exposures conceptualized as risk factors across levels: demographic characteristics; psychological and psychiatric variables; social determinants; cultural and historical contexts (including legacy of colonization and historical trauma); and structural factors such as poverty, healthcare access, and rural isolation. The protocol frames these exposures to capture multilevel determinants that may influence the emergence of NSSI and the transition from ideation to suicidal behavior.
Primary outcomes are non-suicidal self-injury (NSSI) and suicide attempts, defined by suicidal intent: NSSI denotes deliberate self-injury without suicidal intent, while a suicide attempt involves at least some intent to die. Because terminology varies in the literature, the review will also record studies using the term 'self-harm' where intent is unspecified or cannot be determined. The review will capture method-specific outcomes and indicators of clinical severity, including ED presentation, hospitalization, ICU admission, near-fatal attempts, and case fatality when reported.
Eligible study designs include observational and epidemiological research reporting incidence, prevalence, associations, or descriptive data on NSSI and suicide attempts among AI/AN youth. Interventional studies are not the primary focus unless they report relevant baseline or observational data that meet inclusion criteria.
Electronic databases to be searched from inception are MEDLINE via PubMed, Embase, PsycINFO, CINAHL, and the Web of Science Core Collection. The protocol states that searches will capture relevant observational and epidemiological studies; details of search terms and strategies are provided in the protocol supplementary material (PRISMA-P aligned search specification). The authors plan to include studies published in any year from database inception and to document the search process in the final review.
Two reviewers will independently screen titles and abstracts, review full texts, and extract data. The reviewers named in the protocol are AS and YZ; they will work in duplicate to reduce selection bias. Extracted data will include study characteristics, population details, measured risk factors, method distributions, and indicators of clinical severity. The team will record reasons for exclusion at full-text review and will document the screening process following PRISMA flow conventions.
Methodological quality of included studies will be appraised using Joanna Briggs Institute critical appraisal tools appropriate for each study design. The overall certainty of the evidence will be evaluated using the GRADE framework. Risk-of-bias assessments and GRADE ratings will be reported in the completed review.
A narrative synthesis of findings across multilevel risk factors, method distributions, and severity indicators will be undertaken. Where data are sufficiently homogeneous and appropriate, the authors will conduct random-effects meta-analyses. The protocol commits to reporting heterogeneity and to using statistical pooling only when justified. The review will integrate epidemiological, developmental, and structural perspectives to interpret findings for the 10–25 age range.
This planned systematic review aims to fill a critical gap: no prior review has simultaneously focused on AI/AN adolescents and young adults (10–25 years), synthesized multilevel risk factors within a structured framework, and examined method distribution alongside indicators of attempt severity and lethality. The authors anticipate that results will inform culturally responsive prevention strategies, support Tribal and Indian Health Service planning, and strengthen equity-focused public health efforts to reduce disparities in suicide attempts among AI/AN youth.
The protocol is prospectively registered on OSF (Registration ID: rjf2u). The authors report that no datasets were generated or analyzed for this protocol paper. They declare no specific funding for the work and state that no competing interests exist. The authors indicate intent to follow reporting guidelines and to transparently document any protocol changes in the OSF record.