Measurement Invariance of Perfectionism Measures in Students with and without a History of Non-Suicidal Self-Injury.

Kate E Tonta,Joel Howell,Peter Mcevoy,Penelope Hasking,Mark Boyes

doi:10.3390/ijerph181910171

Abstract

Perfectionism is a transdiagnostic process which may be implicated in the onset and maintenance of non-suicidal self-injury. No study has evaluated whether reported differences in perfectionism between individuals with and without a history of self-injury represent genuine group differences or measurement artefacts. The present study reports an investigation of the measurement invariance of two common scales of perfectionism, the Frost Multidimensional Perfectionism Scale-Brief (FMPS-Brief) and the Clinical Perfectionism Questionnaire (CPQ), among university students (Mage = 20.48, SDage = 2.22, 75.3% female, 22.8% male) with and without a history of self-injury (total n = 711). Results revealed full residual error invariance for the two-factor model of FMPS-Brief, while the bifactor model of the FMPS-Brief and the two-factor model of the CPQ demonstrated partial metric invariance. Accounting for partial metric invariance, the bifactor model of the FMPS-Brief also demonstrated partial residual error invariance. The current findings suggest that observed differences using the FMPS-Brief reflect genuine differences in perfectionism between individuals with and without a history of self-injury. Further, while researchers using the bi-factor model can have confidence that the general factor can adequately assess group differences, differential item functioning should be considered if using the strivings and concerns factors. Finally, in the current data, the CPQ did not perform as expected in baseline model fit and future research should replicate assessments of measurement invariance in this measure.

Highlights

In 2019, more than one in every 100 deaths worldwide was by suicide [1], with a representative sample indicating that over half of the Australian population reported exposure to suicide of someone known to them [2]
Suicide are functionally distinct behaviours in that non-suicidal self-injury (NSSI) is non-suicidal in intent, frequency of NSSI and the number of methods used to self-injure have been identified in meta-analytic research as important predictors of suicide behaviour [4,5]
In non-clinical adult samples, research using multidimensional models of perfectionism has shown mixed associations, with some subscales of perfectionism strongly associated, while other subscales showed no significant association [20]. These findings indicate that perfectionism is likely an important process related to NSSI, the measurement of perfectionism is inconsistent across studies, with some research using multidimensional models [20] and others using subscales of larger measures of eating disorder pathologies [19]

Summary

Introduction

In 2019, more than one in every 100 deaths worldwide was by suicide [1], with a representative sample indicating that over half of the Australian population reported exposure to suicide of someone known to them [2]. Understanding risk factors associated with future suicidal ideation and behaviour is critical for prevention and intervention efforts. One such factor is non-suicidal self-injury (NSSI), which is deliberately damaging one’s body tissue without suicidal intent and in a way that is not culturally sanctioned [3]. NSSI and suicide are functionally distinct behaviours in that NSSI is non-suicidal in intent, frequency of NSSI and the number of methods used to self-injure have been identified in meta-analytic research as important predictors of suicide behaviour [4,5]. The most commonly reported function of NSSI is to regulate intense or unwanted emotions, and NSSI has been identified as an important area for further research [6]. Only a small proportion of individuals seek urgent care relating

Methods

Results

Discussion

Conclusion