ImportanceSuicide rates among adolescents continue to rise, but there are a lack of clinical tools to predict when youths may be at risk for suicidal behaviors.ObjectiveTo identify whether geolocation metrics, assessed through an app installed on adolescents’ personal smartphones, could detect the risk of next-week suicidal events and clinically meaningful suicidal ideation.Design, Setting, and ParticipantsThis case series study included high-risk adolescents aged 13 to 18 years reporting a current affective and/or substance use disorder, oversampled for suicidal thoughts and behaviors (STB). Participants were recruited from the greater New York City and Pittsburgh communities through psychiatric outpatient programs, emergency departments, medical center research registries, and social media. Participants installed the Effortless Assessment Research System (EARS) software application onto their personal smartphones, which obtained passive sensor data, including geolocation metrics (via the global positioning system [GPS]), as well as weekly experience sampling data probing STB for the duration of the 6-month study. Adolescents also completed clinical assessments at baseline as well as during the 1-, 3-, and 6-month follow-up assessments. Statistical analysis was performed from March 2023 to November 2024.Main Outcomes and MeasuresRepeated measures mixed-effects logistic models estimated whether weekly aggregates of geolocation features (ie, entropy, homestay, distance traveled) were associated with next-week suicidal events (ie, suicide attempts, psychiatric hospitalizations, emergency department visits for suicide concerns) and clinically meaningful ideation (via weekly experience sampling).ResultsOverall, 186 participants were included in this study (148 [79.6%] female; 19 [10.2%] Asian, 23 [12.4%] Black, and 106 [57.0%] White), with a mean (SD) age of 16.4 (1.7) years. Greater homestay (amount of time spent at home) on a given week, relative to one’s own mean, was associated with 2-fold greater odds of suicidal events during the subsequent week (odds ratio, 1.99 [95% CI, 1.15-3.45]). Results were not significant for entropy and distance traveled metrics. However, using leave-future-out validation, the accuracy of the homestay model was modest (area under the receiver operating characteristic curve, 0.64 [95% CI, 0.50-0.78]).Conclusions and RelevanceAdvancements in smartphone technology afford unique opportunities to capture affective and behavioral dynamics that presage suicide risk. This case series study found that greater homestay obtained through smartphone GPS data over the course of a week, relative to one’s own mean, was associated with greater odds of a suicidal event in the subsequent week. Although accuracy was modest, these findings offer a novel starting point for suicide prevention research, particularly as smartphone sensor data may have the capacity to identify who is at risk while also providing an opportunity to deliver clinical tools when that risk is greatest.

Adolescent suicide is a public health emergency with interpersonal factors playing a critical role in risk for suicidal thoughts and behaviors (STB). This study examined whether smartphone-based ecological momentary assessment (EMA) surveys capturing stress and social context could enhance the identification of youth at risk for STB. Adolescents ages 13-18-years-old (N = 207, 166 female sex) reporting depressive, anxiety, and/or substance use disorders were recruited from psychiatric outpatient programs, emergency departments, medical research registries, and social media. Participants with STB history were oversampled; 66 % reported current suicidal ideation and 27 % had a past-year attempt. Assessments of suicidal events (attempts, emergency department visits, hospitalizations for suicide concerns) were completed at baseline, 1-, 3-, and 6-month follow-up assessments. EMA probed momentary stress severity, affect, and recent social context (time spent with peers, family, or alone) 4-7×/day. Compared to psychiatric controls (N = 64), adolescents with STB history (N = 143) were more likely to report spending time alone (aOR = 1.75, 95 % CI = [1.15, 2.39]), less time with family (aOR = 0.59, 95 % CI = [0.31, 0.91]), and higher stress (d = 0.28). Further, EMA of stress (aOR = 1.86, 95 % CI = [1.11, 3.26]) and negative affect (aOR = 2.32, 95 % CI = [1.34, 4.36]) were prospectively associated with suicidal events above and beyond prior STB history. Broadly, results were similar between EMA measures of stress and negative affect, indicating such responses may reflect shared underlying processes. These findings underscore the importance of evaluating dynamic family and peer contact among adolescents at risk for STB and highlight EMA as a potential tool for assessing interpersonal exposures related to STB risk. Preprint link: doi:10.31234/osf.io/kepxw.

Intensive longitudinal research–including experience sampling and smartphone sensor monitoring–has potential for identifying proximal risk factors for psychopathology, including suicidal thoughts and behaviors (STB). Yet, missing data can complicate analysis and interpretation. This study aimed to address whether clinical and study design factors are associated with missing data, and whether missingness predicts changes in symptom severity or STB. Adolescents ages 13-18-years-old (N=179) reporting depressive, anxiety, and/or substance use disorders were enrolled; 65% reported current suicidal ideation and 29% indicated a past-year attempt. Passively acquired smartphone sensor data (e.g., GPS, accelerometer, keyboard inputs), daily mood surveys, and weekly suicidal ideation surveys were collected during the 6-month study period using the Effortless Assessment Research System (EARS) smartphone app. First, acquisition of passive smartphone sensor data (with data on ~80% of days across the whole sample) was strongly associated with survey data acquisition the same day (~44% of days). Second, STB and psychiatric symptoms were largely not associated with missing data. Rather, temporal features (e.g., length of time in study, weekends, summer) explained more missingness of survey and passive smartphone sensor data. Last, within-participant changes in missing data over time neither followed nor predicted subsequent change in suicidal ideation and psychiatric symptoms. Findings indicate that considering technical and study design factors impacting missingness is critical and highlight several factors that should be addressed to maximize the validity of clinical interpretations in intensive longitudinal research.

Background: Suicide is a major public health crisis among youth. Several prominent theories, including the Interpersonal Theory of Suicide (IPTS), aim to characterize the factors leading from suicide ideation to action. These theories are largely based on findings in adults and require testing and elaboration in adolescents. Methods: Data were examined from high-risk 13-18-year-old adolescents (N = 167) participating in a multi-wave, longitudinal study; 63% of the sample exhibited current suicidal thoughts or recent behaviors (n = 105). The study included a 6-month follow-up period with clinical interviews and self-report measures at each of the four assessments as well as weekly smartphone-based assessments of suicidal thoughts and behaviors. Regression and structural equation models were used to probe hypotheses related to the core tenets of the IPTS. Results; Feelings of perceived burdensomeness were associated with more severe self-reported suicidal ideation (b = 0.58, t(158) = 7.64, p < .001). Similarly, burdensomeness was associated with more frequent ideation based on weekly smartphone ratings (b = 0.11, t(1460) = 3.41, p < .001). Contrary to IPTS hypotheses, neither feelings of thwarted belongingness, nor interactions between burdensomeness and thwarted belongingness were significantly associated with ideation (ps > .05). Only elevated depression severity was associated with greater odds of suicide events (i.e., suicide attempts, psychiatric hospitalizations, and/or emergency department visits for suicide concerns) during the follow-up period (OR = 1.83, t(158) = 2.44, p = .01). No effect of acquired capability was found. Conclusions: Perceptions of burdensomeness to others reflect a critical risk factor for suicidal ideation among high-risk adolescents. Null findings with other IPTS constructs may suggest a need to adopt more developmentally sensitive models or measures of interpersonal and acquired capability risk factors for youth. Refining methods and theoretical models of suicide risk may help improve the identification of high-risk cases and inform clinical intervention.

OBJECTIVE:Suicide is a leading cause of death among adolescents. However, there are no clinical tools to detect proximal risk for suicide. METHOD:Participants included 13- to 18-year-old adolescents (N = 103) reporting a current depressive, anxiety, and/or substance use disorder who owned a smartphone; 62% reported current suicidal ideation, with 25% indicating a past-year attempt. At baseline, participants were administered clinical interviews to assess lifetime disorders and suicidal thoughts and behaviors (STBs). Self-reports assessing symptoms and suicide risk factors also were obtained. In addition, the Effortless Assessment of Risk States (EARS) app was installed on adolescent smartphones to acquire daily mood and weekly suicidal ideation severity during the 6-month follow-up period. Adolescents completed STB and psychiatric service use interviews at the 1-, 3-, and 6-month follow-up assessments. RESULTS:K-means clustering based on aggregates of weekly suicidal ideation scores resulted in a 3-group solution reflecting high-risk (n = 26), medium-risk (n = 47), and low-risk (n = 30) groups. Of the high-risk group, 58% reported suicidal events (ie, suicide attempts, psychiatric hospitalizations, emergency department visits, ideation severity requiring an intervention) during the 6-month follow-up period. For participants in the high-risk and medium-risk groups (n = 73), mood disturbances in the preceding 7 days predicted clinically significant ideation, with a 1-SD decrease in mood doubling participants' likelihood of reporting clinically significant ideation on a given week. CONCLUSION:Intensive longitudinal assessment through use of personal smartphones offers a feasible method to assess variability in adolescents' emotional experiences and suicide risk. Translating these tools into clinical practice may help to reduce the needless loss of life among adolescents.