Conceptualization, development and validation of T‐QoL^©(Teenagers’ Quality of Life): a patient‐focused measure to assess quality of life of adolescents with skin diseases

Abstract

SummaryBackground Skin disease can affect the quality of life (QoL) of teenagers in a variety of different ways, some being unique to this age group. Objectives To develop and validate a dermatology-specific QoL instrument for adolescents with skin diseases. Methods Qualitative semistructured interviews were conducted with adolescents with skin disease to gain in-depth understanding of how skin diseases affect their QoL. A prototype instrument based on the themes identified from content analysis of interviews was tested in several stages, using classical test theory and item response theory models to develop this new tool and conduct its psychometric evaluation. Results Thirty-three QoL issues were identified from semistructured interviews with 50 adolescents. A questionnaire based on items derived from content analysis of interviews was subjected to Rasch analysis: factor analysis identified three domains, therefore not supporting the validity of T-QoL as a unidimensional measure. Psychometric evaluation of the final 18-item questionnaire was carried out in a cohort of 203 adolescents. Convergent validity was demonstrated by significant correlation with Skindex-Teen and Dermatology Life Quality Index (DLQI) or Children's DLQI. The T-QoL showed excellent internal consistency reliability: Cronbach's a = 0Á89 for total scale score and 0Á85, 0Á60 and 0Á74, respectively, for domains 1, 2 and 3. Test-retest reliability was high in stable volunteers. T-QoL showed sensitivity to change in two subgroups of patients who indicated change in their self-assessed disease severity. Conclusions Built on rich qualitative data from patients, the T-QoL is a simple and valid tool to quantify the impact of skin disease on adolescents' QoL; it could be used as an outcome measure in both clinical practice and clinical research.

The Evolution of Quality of Life Assessment and Use in Dermatology

“…It remains the only dermatology-specific QoL instrument for this age group. Two dermatology-specific instruments for adolescents with skin diseases were developed [19, 20] but have not yet been used in other published studies. Several disease-specific instruments (predominantly atopic dermatitis-specific) for children and their parents were developed.…”

T‐QoL: a quality of life outcome measure specifically developed for adolescents with skin diseases

“…The T‐QoL seems to be responsive, but future studies with larger sample sizes are required. Further, the T‐QoL was found to be easy to understand and administer . Herewith, this new quality of life instrument is promising for use in adolescents with different skin diseases.…”

“…In this issue of the BJD , Basra and colleagues developed and validated the Teenagers’ Quality of Life (T‐QoL) – a new instrument that can be used to assess the impact of skin disease on teenagers’ quality of life . Semi‐structured interviews were conducted among 50 adolescents with eczema, which support the content validity of the instrument.…”

“…However, patients included in the present study by Basra et al . were predominantly patients with acne ( n = 105), and only 31 patients with eczema were included (besides patients with moles, psoriasis, warts and nonspecific dermatitis) . For the T‐Qol to be taken into consideration and become an instrument with the potential to be included in the core outcome set, i.e.…”

Psoriasis has a huge impact on teenagers

“…A psoriasis‐specific instrument designed to measure the impairment of health‐related quality of life (HRQoL) in adolescents is lacking, and until recently, a dermatology‐specific instrument, specifically designed for this age group (other than adapted from an adult version) was unavailable . Clinicians, familiar with adult measures, might focus on domains irrelevant for adolescents, or may not be aware of differences in HRQoL, and thus not address important, adolescent‐specific issues.…”