Real-time monitoring of the associations between self-critical and self-punishment cognitions and nonsuicidal self-injury

A multi-modal assessment of self-knowledge in adolescents with non-suicidal self-injury: a research domains criteria (RDoC) study

BACKGROUND

Adolescence is a critical period for brain development, consolidation of self-understanding, and onset of non-suicidal self-injury (NSSI). This study evaluated the RDoC (Research Domain Criteria) sub-construct of Self-Knowledge in relation to adolescent NSSI using multiple units of analysis.

METHODS

One hundred and sixty-four adolescents assigned female at birth (AFAB), ages 12-16 years with and without a history of NSSI entered a study involving clinical assessment and magnetic resonance imaging (MRI), including structural, resting-state functional MRI (fMRI), and fMRI during a self-evaluation task. For imaging analyses, we used an a priori defined Self Network (anterior cingulate, orbitofrontal, and posterior cingulate cortices; precuneus). We first examined interrelationships among multi-level Self variables. We then evaluated the individual relationships between NSSI severity and multi-level Self variables (self-report, behavior, multi-modal brain Self Network measures), then conducted model testing and multiple regression to test how Self variables (together) predicted NSSI severity.

RESULTS

Cross-correlations revealed key links between self-reported global self-worth and self-evaluation task behavior. Individually, greater NSSI severity correlated with lower global self-worth, more frequent and faster negative self-evaluations, lower anterior Self Network activation during self-evaluation, and lower anterior and posterior Self Network resting-state connectivity. Multiple regression analysis revealed the model including multi-level Self variables explained NSSI better than a covariate-only model; the strongest predictive variables included self-worth, self-evaluation task behavior, and resting-state connectivity.

CONCLUSIONS

Disruptions in Self-Knowledge across multiple levels of analysis relate to NSSI in adolescents. Findings suggest potential neurobiological treatment targets, potentially enhancing neuroplasticity in Self systems to facilitate greater flexibility (more frequently positive) of self-views in AFAB adolescents.

Longitudinal Associations Between Negative Body Image, Self-Disgust, and Nonsuicidal Self-Injury Among Chinese Adolescents: Disentangling Between- and Within-Person Effects

Nonsuicidal self-injury (NSSI) and negative body image are both highly prevalent among adolescents, and there are theoretically proposed reciprocal associations between them. However, previous research has not differentiated between stable personal traits and time-varying state levels when examining these associations, and the underlying mechanisms remain unclear. To address these gaps, this study investigated the longitudinal associations between negative body image, self-disgust, and NSSI among Chinese adolescents, disentangling the between- and within-person effects by employing random intercept cross-lagged panel models (RI-CLPMs). A total of 515 Chinese adolescents (50.7% boys; baseline Mage = 12.34 years, SD = 0.47) participated in a four-wave longitudinal study with 6-month intervals. The results indicated that, at the between-person level, higher levels of self-disgust were associated with more NSSI and more concerns about general appearance, facial appearance, shortness, and fatness, but were not associated with concerns about thinness. At the within-person level, general appearance concern and NSSI positively predicted each other over time through self-disgust. Concerns about facial appearance, shortness, and fatness all positively predicted self-disgust, which in turn positively predicted NSSI over time, but not vice versa. These findings highlight the stable and trait-like associations between self-disgust, NSSI, and most negative body image dimensions. Self-disgust is worth considering as a target for intervention, as it plays a mediating role in the long-term associations between negative body image and NSSI.

"I'm so dumb and worthless right now": factors associated with heightened momentary self-criticism in daily life

Self-criticism is a trait associated with increased psychopathology, but self-criticism is also a personality state reflecting an action that people do in moments of time. In the current study, we explored factors associated with heightened self-criticism in daily life. Participants (N = 197) received five random prompts per day for one week on their mobile phones, where they reported their current affect (negative and positive affect), willpower self-efficacy, distress intolerance, degree of support and criticism from others, current context (location, activity, hunger, tiredness) and momentary self-criticism. We first demonstrated that self-criticism varies over time and across contexts, and is associated with heightened trait self-criticism. Then, using multilevel modelling, we explored the contextual factors associated with greater self-criticism. We found that self-criticism was higher when people were at home, and more tired. We also found higher self-criticism to be associated with greater negative and lower positive affect, greater distress intolerance, lower willpower and greater perceived criticism from others. In addition, self-criticism predicted subsequent distress intolerance, willpower and positive affect in lagged analyses. This study provides evidence that both environmental and psychological factors are associated with the dynamics of self-critical thoughts.

A Brief Cognitive Analytic Therapy-Informed Approach for Young People That Have Self-Injured (CATCH-Y): A Case Series

BACKGROUND

Non-suicidal self-injury (NSSI) presents an increasingly prevalent problem for young people; however, there remains a scarce evidence base for effective, scalable treatments for adolescents. This study aimed to assess the feasibility and acceptability of a brief, cognitive analytic therapy (CAT)-informed intervention for young people who engage in NSSI (CATCH-Y).

METHODS

A case series design recruited 13 young people who met the inclusion and exclusion criteria to participate in the five-session intervention. Eligible participants were aged 13-17 years (M = 15.15, SD = 1.28) and had engaged in NSSI at least once in the previous 6 months. Feasibility and acceptability were measured via recruitment, retention, qualitative feedback and missing data. The secondary outcome measures of personal recovery and motivation were administered pre- and post-assessment, with measures of depressive symptoms and urges to self-injure.

RESULTS

The intervention was found to be largely feasible and acceptable with high rates of recruitment, retention and pre-/post-assessment data completeness. Measures showed preliminary support for positive change in rates of NSSI, urges to self-harm, low mood and personal recovery, although results were mixed. Completion rates for remote assessments were low.

CONCLUSIONS

The findings of this study support further evaluation of the CATCH-Y intervention on a larger scale. In-person assessments may be preferable to remote to ensure good completion rates.

A Comparison of Affective-Cognitive States in Daily Life Between Emerging Adults With and Without Past-Year Nonsuicidal Self-Injury

Although the literature suggests trait-like differences in affective and cognitive vulnerabilities between individuals with and without a history of nonsuicidal self-injury (NSSI), little is known about how these dispositional differences are experienced in the natural environment. The present study compares the intensity, inertia, interaction, and variability of affective (negative and positive affect) and cognitive states (rumination, self-criticism) in the everyday lives of individuals who do and do not engage in NSSI. Using experience sampling methodology (ESM), 60 emerging adults (ages = 18-22 years) with and without past-year NSSI (equally distributed) completed eight questionnaires per day for 12 days (in total, 96 questionnaires per participant), resulting in 4,587 assessments (median compliance = 83.3%; IQR = 71.9-91.7). In a dynamic structural equation modeling framework, dynamic parameters (i.e., mean intensity, carryover effects, spillover effects, and within-person variability) were evaluated using multilevel vector autoregressive models. Emerging adults who engage in NSSI experience higher intensity and greater variability of negative affect, rumination, and self-criticism, whereas those who do not engage in NSSI experience higher intensity and lower variability of positive affect. In addition, past-year NSSI predicted stronger affective-cognitive interactions over time, with stronger spillover effects of negative and positive affect on subsequent rumination and self-criticism in individuals who engage in NSSI. Depressive symptoms and trait levels of emotion dysregulation and self-criticism partially negated these differences. Our findings provide evidence that emerging adults who self-injure experience more negative affective-cognitive states in daily life and point to the potential relevance of boosting positive emotions to buffer negative cognitions.

Examining state self-criticism and self-efficacy as factors underlying hopelessness and suicidal ideation

INTRODUCTION

When people feel hopeless, they are more likely to think about suicide. Prior work has shown that both hopelessness and suicidal ideation fluctuate over time; however, there are likely other contextual factors underlying increased hopelessness and suicidal ideation in moments of time.

METHOD

In two studies using retrospective recall of a real event (Study 1, n = 268) and an experimental imaginal vignette design (Study 2, n = 356), we examined self-criticism and self-efficacy for self-regulation as crucial factors underlying hopelessness in people vulnerable to suicidal ideation.

RESULTS

In both studies, greater state self-criticism and lower state self-efficacy were associated with greater hopelessness. In Study 2, we also measured suicidal ideation, and found that higher self-criticism and lower self-efficacy for self-regulation scores were associated with greater suicidal ideation, even when controlling for negative affect. Evidence of an interaction between self-criticism and self-efficacy was found with scores in Study 2 but not in Study 1; specifically, lower self-efficacy was associated with greater ideation when self-criticism was high but not when self-criticism was low.

CONCLUSION

Overall, results support self-criticism and self-efficacy as important contextual factors underlying hopelessness and suicidal ideation and attending to the potential interactive effect between self-criticism and self-efficacy.

The Effect of Bullying Victimization on Adolescent Non-Suicidal Self-Injury: The Mediating Roles of Alexithymia and Self-Esteem

Background & Aim

Non-suicidal self-injury (NSSI) in adolescents is a serious public health issue influenced by the interaction of multiple factors. The purpose of this study was to investigate the multiple mediating roles of alexithymia and self-esteem in the association between bullying victimization and NSSI in a sample of Chinese adolescents.

Methods

A survey of 1299 adolescents from two public middle schools in Henan Province, China, was undertaken. Data were collected using the Chinese version of the Delaware bullying victimization scale-student (DBVS-S), the Toronto Alexithymia-20 Scale (TAS-20-C), the Rosenberg self-esteem scale (RSES), and the adolescent self-injury questionnaire. Besides, we performed a structural equation modeling (SEM) with latent variables using AMOS 26.0 to examine the relationship between variables and the mediating effects.

Results

The SEM analysis found that not only can bullying victimization directly impact NSSI, but that alexithymia and self-esteem have a chain mediating effect in the association between bullying victimization and NSSI. This mediating effect contributed 22.47% to the total effect.

Conclusion

These findings validate bullying victimization, alexithymia, and low self-esteem are important variables that affect NSSI among Chinese adolescents. Educators need to implement some prevention and intervention strategies to ameliorate the campus atmosphere and adolescents' mental health aimed at avoiding NSSI behavior in adolescence.

Social stressors, emotional responses, and NSSI urges and behaviors in daily life

BACKGROUND

The defective self model of nonsuicidal self-injury (NSSI) theorizes that individuals who are highly self-critical are more likely to choose NSSI to regulate emotions. This model indirectly suggests that individuals who engage in NSSI may experience more self-conscious emotions in response to negative social feedback, increasing risk for near-term NSSI. This study examined (1) whether individuals with a history of NSSI (vs. without) display greater self-conscious and negative emotional reactions to daily social stressors, and more problematic features of these daily social stressors, and (2) whether greater-than-usual negative emotional reactions and social stressor features predict NSSI urges and behaviors in daily life.

METHODS

Participants were 134 female college students with recent, recurrent NSSI (n = 77) or no NSSI history (n = 57). Participants completed baseline measures of socioemotional functioning and a two-week daily diary protocol.

RESULTS

The NSSI (vs. no NSSI) group reported significantly greater self-conscious and negative emotional reactions to daily social stressors, and social stressors characterized by greater dysfunction. In the NSSI group, experiencing social stressors characterized by greater distress than one's average during the daily diary period was associated with same-day NSSI urges and behavior, greater confusion than one's average predicted same-day NSSI urges, and greater conflict than one's average predicted same-day NSSI behavior. Greater self-conscious and negative emotional reactions to these stressors than one's average predicted same-day NSSI urges and behavior.

LIMITATIONS

Limitations include reliance on self-report, a once-daily assessment, and lack of generalizability to other samples.

CONCLUSIONS

Interpersonal conflict and increased self-conscious emotions pose vulnerability for NSSI. Prevention and intervention efforts would benefit from including a focus on interpersonal functioning.

A Longitudinal Examination of Recent Posttraumatic Stress Symptoms and Nonsuicidal Self-Injury among University Students

Nonsuicidal self-injury is a burgeoning mental health concern amongst post-secondary students. In the present study, the link between posttraumatic stress symptoms (PTSS) and nonsuicidal self-injury (NSSI) was examined among post-secondary students over time, while accounting for the role of co-occurring depressive symptoms. Participants were 841 first-year university students with self-reported lifetime histories of trauma who reported on traumatic experiences, PTSS, depressive symptoms, and NSSI at three time points over the course of their first year of university. This study also included exploratory correlational analyses of the relation among PTSS and motivations for NSSI engagement. As expected, PTSS predicted NSSI engagement among students within and across time, though effects were small. The strongest correlations were among PTSS and engaging in NSSI for the purposes of fulfilling self-punishment desires and anti-dissociation (e.g., to reduce feelings of numbness). This study provides further support for theories underscoring NSSI as a means of coping with intra- and interpersonal distress among post-secondary students experiencing stressful life events, such as trauma.

The Effects of Self-Criticism and Self-Compassion on Adolescents' Depressive Symptoms and Nonsuicidal Self-Injury

Purpose

Symptoms of depression increase during adolescence as do nonsuicidal self-injurious behaviors (NSSI). The present study aimed to investigate how self-criticism interacted with the effects of stressful life events on depressive symptoms and NSSI and whether self-compassion would buffer these negative effects.

Methods

A total of 908 Chinese adolescents (Mage = 13.46, SD = 0.57) completed a cross-sectional survey. The main and interacted effects of stressful life events, self-criticism, self-compassion on depressive symptoms and NSSI were examined respectively.

Results

The results showed that self-criticism significantly moderated the relationships between stressful events and depression and NSSI. Self-compassion could buffer the negative impacts of stressful events and self-criticism on NSSI but not on depression. High self-compassion significantly reduced the magnitude of the association between stressful life events and NSSI in adolescents with low self-criticism but not in those with high self-criticism.

Conclusion

Self-criticism exacerbated the negative impacts of stressful life events on both depressive symptoms and NSSI, but self-compassion only buffered the impact of stressful life events on NSSI. Interventions designed to reduce NSSI risk of Chinese adolescents may benefit from training them to improve self-compassion abilities and to be less self-critical.

The Detection of Acute Risk of Self-injury Project: Protocol for an Ecological Momentary Assessment Study Among Individuals Seeking Treatment

BACKGROUND

Nonsuicidal self-injury (NSSI) is a major mental health concern. Despite increased research efforts on establishing the prevalence and correlates of the presence and severity of NSSI, we still lack basic knowledge of the course, predictors, and relationship of NSSI with other self-damaging behaviors in daily life. Such information will be helpful for better informing mental health professionals and allocating treatment resources. The DAILY (Detection of Acute rIsk of seLf-injurY) project will address these gaps among individuals seeking treatment.

OBJECTIVE

This protocol paper presents the DAILY project's aims, design, and materials used. The primary objectives are to advance understanding of (1) the short-term course and contexts of elevated risk for NSSI thoughts, urges, and behavior; (2) the transition from NSSI thoughts and urges to NSSI behavior; and (3) the association of NSSI with disordered eating, substance use, and suicidal thoughts and behaviors. A secondary aim is to evaluate the perspectives of individuals seeking treatment and mental health professionals regarding the feasibility, scope, and utility of digital self-monitoring and interventions that target NSSI in daily life.

METHODS

The DAILY project is funded by the Research Foundation Flanders (Belgium). Data collection involves 3 phases: a baseline assessment (phase 1), 28 days of ecological momentary assessment (EMA) followed by a clinical session and feedback survey (phase 2), and 2 follow-up surveys and an optional interview (phase 3). The EMA protocol consists of regular EMA surveys (6 times per day), additional burst EMA surveys spaced at a higher frequency when experiencing intense NSSI urges (3 surveys within 30 minutes), and event registrations of NSSI behavior. The primary outcomes are NSSI thoughts, NSSI urges, self-efficacy to resist NSSI, and NSSI behavior, with disordered eating (restrictive eating, binge eating, and purging), substance use (binge drinking and smoking cannabis), and suicidal thoughts and behaviors surveyed as secondary outcomes. The assessed predictors include emotions, cognitions, contextual information, and social appraisals.

RESULTS

We will recruit approximately 120 individuals seeking treatment aged 15 to 39 years from mental health services across the Flanders region of Belgium. Recruitment began in June 2021 and data collection is anticipated to conclude in August 2023.

CONCLUSIONS

The findings of the DAILY project will provide a detailed characterization of the short-term course and patterns of risk for NSSI and advance understanding of how, why, and when NSSI and other self-damaging behaviors unfold among individuals seeking treatment. This will inform clinical practice and provide the scientific building blocks for novel intervention approaches outside of the therapy room that support people who self-injure in real time.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/46244.

Investigation of the Subtypes of Nonsuicidal Self-Injury Based on the Forms of Self-Harm Behavior: Examining Validity and Utility via Latent Class Analysis and Ecological Momentary Assessment

BACKGROUND

This study aimed to empirically derive and validate subtypes of nonsuicidal self-injury (NSSI) based on the forms of self-harm behavior.

METHODS

Sixty young adults who exhibited repetitive NSSI completed a clinical interview and baseline measures, followed by a two-week ecological momentary assessment (EMA). A latent class analysis was administered to identify NSSI subtypes based on the forms of self-harm behavior. The subtypes were then compared to baseline clinical and EMA variables, including emotions and urges to self-harm.

RESULTS

The best-fitting model supported two subtypes: 1) substance abuse and suicide attempt subtype and 2) cutting and scratching subtype. The substance abuse and suicide attempt subtype reported a higher rate of engaging in lifetime suicide plans and suicide attempts and a higher number of lifetime suicide attempts. They also showed significantly higher severity of self-harm behavior, borderline personality traits, anger, posttraumatic symptoms, and difficulties in emotion regulation when compared to the cutting and scratching subtype. However, there was no inter-subtype difference in self-esteem. In the EMA data, anger toward others, feeling of rejection, loneliness, and helplessness were significantly high in the substance abuse and suicide attempt subtype. The variability of anger toward others was also higher in this subtype compared to the cutting and scratching subtype. Finally, in the two-week research period, the substance abuse and suicide attempt group showed a higher rate of reported urges to self-harm with or without suicidal intent.

CONCLUSION

Findings support the validity of the subtypes based on the forms of self-harm behavior, suggesting the clinical utility of addressing heterogeneity within individuals exhibiting self-harm for assessment and treatment.

Non-suicidal self-injury among first-year college students and its association with mental disorders: results from the World Mental Health International College Student (WMH-ICS) initiative

BACKGROUND

Although non-suicidal self-injury (NSSI) is an issue of major concern to colleges worldwide, we lack detailed information about the epidemiology of NSSI among college students. The objectives of this study were to present the first cross-national data on the prevalence of NSSI and NSSI disorder among first-year college students and its association with mental disorders.

METHODS

Data come from a survey of the entering class in 24 colleges across nine countries participating in the World Mental Health International College Student (WMH-ICS) initiative assessed in web-based self-report surveys (20 842 first-year students). Using retrospective age-of-onset reports, we investigated time-ordered associations between NSSI and Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-IV) mood (major depressive and bipolar disorder), anxiety (generalized anxiety and panic disorder), and substance use disorders (alcohol and drug use disorder).

RESULTS

NSSI lifetime and 12-month prevalence were 17.7% and 8.4%. A positive screen of 12-month DSM-5 NSSI disorder was 2.3%. Of those with lifetime NSSI, 59.6% met the criteria for at least one mental disorder. Temporally primary lifetime mental disorders predicted subsequent onset of NSSI [median odds ratio (OR) 2.4], but these primary lifetime disorders did not consistently predict 12-month NSSI among respondents with lifetime NSSI. Conversely, even after controlling for pre-existing mental disorders, NSSI consistently predicted later onset of mental disorders (median OR 1.8) as well as 12-month persistence of mental disorders among students with a generalized anxiety disorder (OR 1.6) and bipolar disorder (OR 4.6).

CONCLUSIONS

NSSI is common among first-year college students and is a behavioral marker of various common mental disorders.

Reliability and Validity of the Self-Rating Scale as a Measure of Self-Criticism

The Self-Rating Scale (SRS; Hooley et al., 2010), a widely used measure of self-criticism in self-injury research, did not utilize conventional test development methods and has limited psychometric data. We examined the internal consistency, test-retest reliability, and convergent and discriminant validity of the SRS. Participants were 295 psychology undergraduate students. The SRS demonstrated good internal consistency (α = .93), adequate test-retest reliability (r = .76), and satisfactory convergent validity with other measures of self-criticism. Convergent validity was also adequate for expected dimensions of perfectionism (socially prescribed, self-oriented, concerns about mistakes, and doubts about actions), depressive symptoms, and negative and positive affect. The SRS demonstrated adequate discriminant validity with expected constructs of perfectionism (other-oriented, personal standards, and organizational perfectionism). Although the SRS appears to be a psychometrically sound measure of self-criticism, high correlations with depression and perfectionism raise questions regarding the overlap of these constructs.

Ecological Momentary Assessment: A Systematic Review of Validity Research

Ecological momentary assessment (EMA) is a self-report method that involves intensive longitudinal assessment of behavior and environmental conditions during everyday activities. EMA has been used extensively in health and clinical psychology to investigate a variety of health behaviors, including substance use, eating, medication adherence, sleep, and physical activity. However, it has not been widely implemented in behavior analytic research. This is likely an example of the empirically based skepticism with which behavioral scientists view self-report measures. We reviewed studies comparing electronic, mobile EMA (mEMA) to more objective measures of health behavior to explore the validity of mEMA as a measurement tool, and to identify procedures and factors that may promote the accuracy of mEMA. We identified 32 studies that compared mEMA to more objective measures of health behavior or environmental events (e.g., biochemical measures or automated devices such as accelerometers). Results showed that the correspondence rates varied considerably across individuals, behavior, and studies (agreement rates ranged from 1.8%-100%), and no unifying variables could be identified across the studies that found high correspondence. The findings suggest that mEMA can be an accurate measurement tool, but further research should be conducted to identify procedures and variables that promote accurate responding.

Different profiles with multiple risk factors of nonsuicidal self-injury and their transitions during adolescence: A person-centered analysis

BACKGROUND

Nonsuicidal self-injury (NSSI) is a serious public health concern among adolescents. However, adolescents with different combinations of NSSI risk factors may constitute different subgroups that vary in subsequent risks of NSSI engagement, and the membership in these subgroups may change during early adolescence. Gender differences related to risk profiles and transition patterns may also exist. This study thus aimed to address these three questions.

METHODS

A total of 2,942 participants ranging from 12 to 17 years old (55.2% females; M_age = 14.60, SD = 1.21) completed a series of questionnaires about NSSI and its risk factors on three occasions, every six months. Latent profile and latent transition analyses were used to examine NSSI risk profiles (subgroups), their transition patterns, and gender differences.

RESULTS

Three distinct risk profiles were identified: Low-risk profile, Medium-risk profile, and High-risk profile. The profile membership was fairly stable over one year, and the shift across profiles represented a "resilient" pattern. Regarding gender differences, boys were less likely to be in either the Medium- or the High-risk groups, but more likely to transition from the Medium- to the Low-risk group, relative to girls.

LIMITATIONS

This study relied upon self-report measures. Additional research is needed to investigate the generalizability of the results to other populations, and to examine more predictors of class membership and transitions.

CONCLUSIONS

The results highlight the importance of considering subgroup differences in understanding NSSI risks. Differentiated interventions with multi-pronged approaches tailoring to different risk classes and gender groups may therefore prove more efficient and effective.

Opening the Black Box of Daily Life in Nonsuicidal Self-injury Research: With Great Opportunity Comes Great Responsibility

Although nonsuicidal self-injury (NSSI)-deliberate damaging of body tissue without suicidal intent-is a behavior that occurs in interaction with real-world contexts, studying NSSI in the natural environment has historically been impossible. Recent advances in real-time monitoring technologies have revolutionized our ability to do exactly that, providing myriad research and clinical practice opportunities. In this viewpoint paper, we review new research pathways to improve our ability to understand, predict, and prevent NSSI, and provide critical perspectives on the responsibilities inherent to conducting real-time monitoring studies on NSSI. Real-time monitoring brings unique opportunities to advance scientific understanding about (1) the dynamic course of NSSI, (2) the real-time predictors thereof and ability to detect acute risk, (3) the ecological validity of theoretical models, (4) the functional mechanisms and outcomes of NSSI, and (5) the promotion of person-centered care and novel technology-based interventions. By considering the opportunities of real-time monitoring research in the context of the accompanying responsibilities (eg, inclusive recruitment, sound and transparent research practices, participant safety and engagement, measurement reactivity, researcher well-being and training), we provide novel insights and resources to open the black box of daily life in the next decade(s) of NSSI research.

Variability in the Functions of Nonsuicidal Self-Injury: Evidence From Three Real-Time Monitoring Studies

Despite functional models of nonsuicidal self-injury (NSSI) helping to explain why people engage in this perplexing behavior, we still lack an understanding of some of the key properties of NSSI functions. Here, we address three unanswered questions about NSSI functions: how much do distinct NSSI functions (1) vary between people over time, (2) vary within people over time, and (3) simultaneously co-occur over time? Data were drawn from three ecological momentary assessment (EMA) studies of self-injurious adult psychiatric outpatients (n = 7), community-based adolescents (n = 15), and community-based adults (n = 9). Across the three studies, there was a total of 271 NSSI episodes (all with corresponding functions captured by EMA). The vast majority (27 of 31; 87%) of participants exhibited unique patterns of NSSI functions during the monitoring periods, indicating high variability between people. The vast majority (26 of 31; 84%) of participants also showed changes in NSSI functions over time, indicating high variability within people. Although it was most common for only one function to be reported for a given NSSI episode, participants endorsed more than one function for 22% to 43% of NSSI episodes, indicating that different functions did simultaneously co-occur. These results underscore that reinforcement processes for NSSI differ from person-to-person, and are both time-varying and multifaceted, which has implications for personalized assessment and treatment of this clinical phenomenon.