Overview
The Young Person’s CORE (YP-CORE) is a brief 10-item self-report measure of general psychological distress and functioning in young people. Designed for routine use in counselling and mental health services, it assesses experiences over the previous week across psychological symptoms, functioning, subjective wellbeing and risk to self. It is intended as a generic outcome measure rather than a diagnostic or disorder-specific questionnaire and is particularly suited to repeated administration for monitoring therapeutic change.Scoring & Interpretation
The YP-CORE contains 10 items referring to experiences over the previous week. Each item is rated from 0–4 using the following response categories: 0 = Not at all; 1 = Only occasionally; 2 = Sometimes; 3 = Often; 4 = Most or all of the time. The two positively worded items are reverse-scored so that higher scores consistently indicate greater psychological distress. The clinical score is calculated by: summing the 10 item scores, producing a range of 0–40. Equivalently, the mean item score can be calculated and multiplied by 10. If one item is missing, current CORE System Trust guidance recommends prorating: Sum completed items ÷ 9 × 10. A clinical score should not normally be calculated if more than one item is missing. There are no separate domain/subscale scores; interpretation is based primarily on the overall YP-CORE score. Clinical cut-offs: Later UK research established age- and gender-specific clinically significant change cut-offs: 11-13 years = Male 10.3; Female 14.4 and 14-16 years = Male 14.1; Female 15.9. Scores need to cross the relevant threshold when determining clinically significant change. Twigg et al. (2016) also derived Reliable Change Indices (RCIs): Male 11–13: 8.3 points; Male 14–16: 8.0 points; Female 11–13: 8.0 points; Female 14–16: 7.4 points. Thus, reliable improvement requires a reduction at least as large as the relevant RCI, while clinically significant improvement additionally requires movement across the appropriate clinical cut-off.Psychometric Properties
Internal Consistency
The original validation demonstrated good internal consistency: Overall Cronbach’s α = .85 (95% CI .82–.88) By gender: Male: α = .83; Female: α = .85.
Reliability remained acceptable across the original age groups: Age 11: α = .72; Age 12: α = .75; Age 13: α = .88; Age 14: α = .87; Age 15: α = .87; Age 16: α = .79. The Twigg et al. (2016) replication reported an overall α = .80, with α greater than .70 across all four age-by-gender groups
Test-Retest Reliability
Not reported in the original 2009 development study. The YP-CORE is principally designed as a change-sensitive outcome measure, meaning that high stability would not necessarily be expected during psychological treatment.
Factor Structure
Principal components analysis in the original study identified two components although these were split into positively worded and negatively worded items and therefore likely reflect item wording direction rather than substantively distinct clinical constructs.
Subsequent psychometric research (O’Reilly et al., 2016)has supported treating the YP-CORE as essentially unidimensional.
Validity
The original development study provided strong preliminary evidence of known-groups/clinical validity and responsiveness to treatment, although it did not conduct a conventional convergent-validity comparison against another established youth mental-health measure.
Measurement Invariance
The original development study did not conduct formal measurement-invariance analysis. However, O’Reilly et al. (2016) subsequently conducted multi-group confirmatory factor analysis and examined invariance across age and gender.
Results supported invariance of: factor structure; factor loadings; item thresholds; and residuals across age and gender, although evidence for strict gender invariance among 12–16-year-olds was partial
Access
The YP-CORE is available directly from theCORE System Trust The CORE System Trust states that CORE instruments, including the YP-CORE, are licensed under:
Creative Commons Attribution–NonCommercial–NoDerivatives 4.0 International (CC BY-NC-ND 4.0).
Thus the measure may be reproduced unchanged for non-commercial purposes without payment or specific permission, provided appropriate attribution is given. New translations, adaptations or derivative versions require permission from the CORE System Trust. http://Official YP-CORE information and download