JMIR Publications

ABSTRACT

Background:

Peer support has long been regarded as an alternative to professional health care resources. Although previous findings on the effects of peer support have been inconclusive, peer support networks (PSNs) for adolescents and young adults appear to offer promising outcomes. However, many existing digital peer support systems operate as proprietary platforms. They offer little transparency about how the effectiveness of support is monitored or how users' personality traits influence outcomes.

Objective:

This study aimed to examine the effects of a digital PSN that connects users based on shared lived experiences on anxiety and perceived social support among Japanese university students. We also explored whether personality traits predict changes in these outcomes.

Methods:

We developed Peer2S, a research platform that matches users based on shared lived experiences while monitoring their mental well-being and personality traits. In a 4-week within-subjects experiment, Japanese university students completed a 2-week baseline control period followed by a 2-week intervention period using the system. Anxiety (7-item Generalized Anxiety Disorder scale [GAD-7]), perceived social support (Multidimensional Scale of Perceived Social Support [MSPSS]), and college-specific social support (Social Support Scale for College Students) were assessed 2 weeks before, at the start of, and at the end of the intervention. Big Five personality traits were assessed using [instrument name]. Outcomes were analyzed using one-way repeated measures ANOVA or Friedman tests, depending on normality, with 2 Bonferroni-corrected post hoc comparisons (control and intervention periods). Multiple regression examined whether personality traits predicted outcome changes during the intervention.

Results:

Of the 28 enrolled students, 25 completed all 3 assessments. GAD-7 scores differed across time points (χ²2=7.10; P=.03; Kendall W=0.14), decreasing significantly during the intervention period (median 7 vs 3; P=[exact value]) but not during the control period (median 5 vs 7; P>.99). MSPSS scores differed across time points (F2,48=4.18; P=.02), with no significant change during the control period (mean 17.36, SD 6.38 vs mean 17.48, SD 6.12; P>.99) and a nonsignificant increase during the intervention (to mean 20.16, SD 5.63; P=.06). College-specific support did not change (all P>.60). In regression analyses (n=23), personality traits explained 45.2% of the variance in anxiety change (adjusted R²=0.29; P=[exact value]). Higher agreeableness predicted less favorable anxiety change (B=0.52; P=.01), and conscientiousness showed a nonsignificant protective association (B=–0.45; P=.06). Personality traits did not predict social support changes (all models P>.50).

Conclusions:

These findings suggest that short-term, algorithmically mediated peer support may yield measurable improvements in mental well-being, particularly reductions in anxiety. The unexpected association between higher agreeableness and increased anxiety may reflect cultural tendencies toward conflict avoidance and overaccommodation in Japan. The varying effects of personality traits highlight the need to consider sociocultural contexts when designing and deploying digital mental health interventions.