Validation of the Pediatric Narcolepsy Screening Questionnaire (PNSQ): A cross-sectional, observational study

Susan Morris; Giuseppe Plazzi; Christine de la Loge; Alexia Marrel; Judi Profant; Teresa L Steininger; Junji Lin; Judith A Owens

doi:10.1016/j.sleep.2022.05.017

Validation of the Pediatric Narcolepsy Screening Questionnaire (PNSQ): A cross-sectional, observational study

Sleep Med. 2022 Oct:98:127-138. doi: 10.1016/j.sleep.2022.05.017. Epub 2022 May 27.

Authors

Susan Morris¹, Giuseppe Plazzi², Christine de la Loge³, Alexia Marrel³, Judi Profant⁴, Teresa L Steininger⁵, Junji Lin⁵, Judith A Owens⁶

Affiliations

¹ Formerly Jazz Pharmaceuticals, Palo Alto, CA, USA. Electronic address: smmorris123@gmail.com.
² Department of Biomedical, Metabolic and Neural Sciences, University of Modena and Reggio-Emilia, Modena, Italy; IRCCS Istituto delle Scienze Neurologiche di Bologna, Bologna, Italy.
³ ICON plc, Lyon, France.
⁴ Formerly Jazz Pharmaceuticals, Palo Alto, CA, USA.
⁵ Jazz Pharmaceuticals, Palo Alto, CA, USA.
⁶ Harvard Medical School, Boston Children's Hospital, Waltham, MA, USA.

PMID: 35834983
DOI: 10.1016/j.sleep.2022.05.017

Abstract

Objective/background: This study evaluated psychometric properties of the Pediatric Narcolepsy Screening Questionnaire (PNSQ), developed in response to the difficulty of identifying pediatric narcolepsy.

Patients/methods: The initial PNSQ was updated following debriefing interviews with parents of children with suspected/diagnosed narcolepsy. Subsequently, newly recruited caregivers were categorized into groups: clinician-confirmed narcolepsy, other sleep problems (OSP), and no sleep problems (controls). Caregivers completed the 11-item PNSQ assessing narcolepsy symptomatology. PNSQ psychometric properties were evaluated; mean PNSQ Total Score (TS) was compared inter-group using analysis of variance.

Results: The analysis population (N = 158) included patients with narcolepsy (n = 49), OSP (n = 55), and controls (n = 54); mean ± SD age was 13.8 ± 2.8, 10.2 ± 4.3, and 10.0 ± 3.8 years, respectively. Inter-item Pearson correlations (range, 0.22-0.75) indicated good construct validity. Principal component analysis confirmed unidimensionality. Item discriminative power was high for narcolepsy vs control (range, 0.693-0.936) and lower for narcolepsy vs OSP (range, 0.584-0.729). The latent trait was well covered (separation index = 0.868). Item 7 (vivid dreams/nightmares), having low discriminative power and specificity, was removed. Cronbach's alpha (final PNSQ) indicated high internal consistency reliability (raw alpha = 0.88). Mean ± SD PNSQ TS (range, 0-50) in the narcolepsy, OSP, and control groups were 34.98 ± 7.98, 25.20 ± 9.43, and 9.54 ± 9.38, respectively (nominal P < 0.0001). Classification by PNSQ TS was defined: PNSQ+ (likely narcolepsy, TS ≥ 29), PNSQ 0 (likely OSP, TS 19-28), and PNSQ- (narcolepsy unlikely, TS ≤ 18); patients with narcolepsy were classified as PNSQ+ (79.6%), PNSQ 0 (18.4%), and PNSQ- (2.0%).

Conclusions: The PNSQ demonstrated good psychometric properties and excellent performance discriminating narcolepsy, OSP, and control groups.

Keywords: Clinical outcome assessment; Pediatric narcolepsy; Psychometric; Screener; Sleep disorders.

Publication types

Observational Study
Research Support, Non-U.S. Gov't

MeSH terms

Child
Cross-Sectional Studies
Humans
Narcolepsy* / diagnosis
Psychometrics
Reproducibility of Results
Surveys and Questionnaires