Phrase-level pairwise topic modeling to uncover helpful peer responses to online suicidal crises

Suicide is a significant public health concern, with rising rates and increasing instances of suicidal ideation and attempts. While national crisis resources exist, limitations in access and concerns about consequences lead many individuals to seek informal support, such as peer support on social media platforms like Reddit's r/SuicideWatch. This platform relies on crowd-sourced interactions, where users experiencing suicidal crises post messages seeking help. This study investigates the quality and content of peer support interactions within this online environment. The Fluid Vulnerability Theory, which posits that suicidality is a dynamic process involving baseline and acute risk, provides a theoretical framework for understanding the importance of timely peer support. Online peer support has been shown to be an effective coping mechanism for various mental health challenges, potentially acting as a catalyst for seeking formal care. However, research on r/SuicideWatch has focused primarily on automated suicide risk detection or descriptive analyses of user posts rather than evaluating the quality of peer support received. This study addresses this gap by examining the content and helpfulness of peer interactions. The research aims to characterize user posts and peer comments, investigate the association between their topics, and determine how these associations influence the perceived helpfulness of peer support, measured by the number of upvotes on Reddit. A secondary aim involves validating findings using data from individuals with a history of suicidal crises.

Existing research on r/SuicideWatch has primarily concentrated on improving automated suicide risk assessment to better triage resources and provide descriptive information on post elements eliciting peer responses. However, there is a lack of studies focused on evaluating the quality of peer support offered. This gap is significant because appropriate support can mitigate crisis states and prevent transitions from suicidal crisis to suicide behavior. The present study seeks to address this gap by providing a more nuanced understanding of the content and quality of peer support within the context of r/SuicideWatch, leveraging a novel methodological approach.

This study employed a two-pronged approach: Study 1 analyzed data from Reddit's r/SuicideWatch, and Study 2 used an independent sample to validate findings. **Study 1:** Data was collected using the Reddit API over 18 months (December 1, 2013, to May 31, 2015), encompassing 21,430 original user posts and 129,008 peer comments. The number of upvotes on peer comments served as a measure of peer-perceived helpfulness. Response time was also calculated. The study introduced PairwiseLDA, a novel topic modeling approach that analyzes user posts and peer comments and their relationships. This method utilizes both words and phrases, identified through the AutoPhrase tool, to improve topic representation. PairwiseLDA accounts for the different number of topics in user posts (K(P)) and peer responses (K(R)) and the association between them. The model employs collapsed Gibbs sampling for inference, with topic number selection based on coherence scores and Maximum Relative Volume Gap (MRVG). Traditional and cross-lingual LDA models were also used for comparison. **Study 2:** Data was collected from Amazon Mechanical Turk (mTurk), recruiting participants through a broader study on emotion, health, and suicidality. The sample comprised 491 participants, with 207 (42.16%) reporting a history of suicidal ideation. Participants answered an open-ended question regarding advice they would give to a friend with suicidal thoughts. Structural topic modeling (Roberts et al., 2013) was applied to the responses, using suicidal ideation history as a covariate to examine topic prevalence.

**Study 1:** Five main topics emerged from user posts: psychological pain, relationship stress, psychiatric disorder, academic difficulty, and financial stress. Ten topics were identified in peer responses: asking questions, communication support, academic encouragement, interest development, life meaning, distraction and entertainment, professional help suggestion, relationship/loss support, thanks and appreciation, and treatment and medication. Analysis revealed that comment length did not significantly correlate with upvotes. However, topic associations significantly influenced perceived helpfulness. While asking questions, communication support, and academic encouragement were frequent, professional help suggestions, life meaning, and relationship/loss support received the most upvotes. The user post topic of financial stress received responses with the highest average number of upvotes, and the user post topic of relationship stress had the second highest. The topic of treatment and medication received the least upvotes. There was a mismatch between the most frequent and the most helpful peer comment topics. **Study 2:** Structural topic modeling identified 12 topics in the independent sample. Eight topics were significantly associated with a history of suicidal crisis. Four topics (seeking professional help, reasons for living, pain caused to others) were less likely used by participants with suicidal ideation history, while four topics (encouragement of professional help, contextualizing suicidal thoughts, direct support, general advice) were more likely used. One topic showed no difference in advice provided between general hardship and suicidal thoughts.

The findings support the Fluid Vulnerability Theory by identifying acute risk factors contributing to suicidal crises, such as relationship problems, academic difficulties, and financial stress. The variety of peer responses, ranging from specific advice to broader support, suggests potential discomfort among peers about providing direct assistance, or an effort to offer individualized support based on personal experiences. The discrepancy between frequent and helpful peer responses highlights the importance of tailoring support to user posts. The independent sample's responses show some consistency (e.g., suggesting professional help) but also differences (e.g., relationship/loss support, reasons for living) in perceived helpfulness compared to r/SuicideWatch peer ratings. The low frequency of professional help suggestions in peer comments suggests a need for education and interventions. The timeliness of peer responses (only 7.8% within 5 minutes) is a crucial concern, given the rapid decision-making process in suicide attempts.

This study provides valuable insights into online peer support during suicidal crises. The findings highlight the importance of considering both user post and peer response topics in determining helpfulness. The discrepancies between frequent and helpful responses suggest the need for educational programs to train peers in providing more effective support, particularly regarding timely professional help suggestions. Future research should focus on directly assessing user perceptions of support and investigating the impact of peer support on suicide crisis outcomes across various online platforms. Further exploration is needed to validate the findings across different demographics and ensure the authenticity of online responses.

The study relied on upvotes and responses from an independent sample as measures of helpfulness, lacking direct assessment of user perception of peer support. Outcome data to assess the impact of peer support on crisis reduction is absent. Findings might not generalize to other online peer support platforms or diverse age groups. The study doesn’t account for the potential presence of non-authentic peer comments. Demographic information characterizing users and peers on r/SuicideWatch is unavailable.