Study design, setting and participants
This is an exploratory study part of the Bangladesh CP Health-related Quality of life (Bangladesh CPQoL) research project. Participants were considered eligible for this study if aged between 10 and 18 years old, a normative classification of adolescence in Bangladesh (21), and were registered with the Bangladesh Cerebral Palsy Register (BCPR) (n=192 at the time of the present study).
BCPR is the first ongoing surveillance program of children with CP in an LMIC. The population-based register covers a defined geographical region of the Shahjadpur sub-district of Sirajganj in the northern part of Bangladesh and holds data on socio-demographic, clinical (including severity, aetiology, associated impairments and risk factors), nutrition, education and rehabilitation status of children and adolescents with CP in Bangladesh.
Key Informant Methodology described in Khandaker, Smithers-Sheedy (22) is used to identify children and adolescents for BCPR.
Adolescent HRQoL and mental health were proxy-reported by primary-caregivers (i.e. parent, grandparent, other relative or close adult friend who provided the majority of their care and support). Adolescents provided self-reported data as part of the broader Bangladesh CPQoL research project however this is not reported for the present study.
Informed verbal and written consent were obtained for all individual participants included in the study. In cases of illiteracy, written consent was obtained by thumbprint. For participants under 16 years, written consent was provided by a parent or guardian. This study adhered to STROBE guidelines and all methods described adhered to the ethical approvals provided by the Bangladesh Medical Research Council (BMRC/NREC/2013-2016/1165) and University of Sydney Human Research Ethics Committee (2016/646).
Demographic and impairment characteristics: Bangladesh Cerebral Palsy Register (BCPR)
We extracted demographic and clinical information about adolescents from the BCPR database including age, sex, type of CP, severity of motor impairment using the gross motor function classification system (GMFCS), other associated impairments, school attendance and proxies of socio-economic status such as monthly family income, household crowding, access to running water and sanitation. Impairments were categorized as yes/ no based on existing diagnosis or presence of impairment during BCPR assessment. GMFCS is a five level classification system; children classified at GMFCS level 1 are independently ambulant whereas children at Level V require wheeled mobility (23). BMI was calculated as weight divided by height and considered underweight if <18.5. Type of housing was defined as Kutcha (houses made from mud, thatch or other organic materials, considered impermanent); semi-pucca housing (made with a combination of materials, considered semi-permanent); and pucca (made from brick, stone, timber or cement, considered permanent). Number of household members was divided by number of rooms to provide persons per room rate of crowding. Non-sanitary latrine was defined as a latrine that discharges into open space.
Health-related quality of life: Cerebral Palsy Quality of Life – Teens (CPQoL-Teens)
Adolescent HRQoL was assessed using the Bengali version of Cerebral Palsy Quality of Life-Teens proxy-report questionnaire (CPQoL-Teens) (24, 25). CPQoL-Teens is a condition specific instrument that uses a nine point Likert scale to assess 88 items across seven dimensions; ‘general wellbeing and participation’, ‘communication and physical health’, ‘school wellbeing’, ‘social wellbeing’, ‘feelings about functioning’, ‘access to services’ (proxy-report only) and ‘family health’ (proxy-report only). Psychometric properties of the Bengali version CPQoL-Teens are available in Power, Akhter 2019 and outcome scores for this sample in Power, Muhit (6).
Adolescent mental health: Strengths and Difficulties Questionnaire
Adolescent mental health was assessed by proxy-reporters using the Bengali version of Strengths and Difficulties questionnaire (SDQ) (26). SDQ is a brief behavioural screening tool that assesses ‘emotional symptoms’, ‘conduct problems’, ‘hyperactivity/ inattention’, ‘peer relationship problems’, and ‘pro-social behaviour’. Adolescent mental health scores for this sample are available in Power, Muhit (6).
Caregiver mental health: Depression, Anxiety and Stress Scale - 21
Caregiver mental health was assessed using the Bengali version of ‘Depression, Anxiety and Stress Scale’ (DASS-21) (27). DASS-21 is a 21-item standardized self-report questionnaire designed to measure the negative related emotional states of ‘depression’, ‘anxiety’ and ‘stress’. Caregiver mental health scores for this sample are available in Power, Muhit (20).
Descriptive statistics were used to summarise the cohort. CPQoL-Teens scores were converted to values between 0 to 100 and mean dimension scores calculated by averaging the items in each dimension; SDQ scores were summed into dysfunction scales and ‘total difficulties score’ calculated by summing the scales; DASS-21 scores were summed into ‘depression’, ‘anxiety’ and ‘stress’ scales and multiplied by two according to the instrument protocol. Data was assessed for normality using Shapiro Wilk and visual inspection of residual plots.
Hierarchical multiple linear regressions (HMLR) were used to determine predictors of each CPQoL-Teens dimension. Potential predictor variables for each model were selected on the basis of theoretical and statistical interests; initially, the research team conducted a systematic review, to identify current knowledge about the self- and proxy-reported HRQoL of adolescents with CP in LMICs, see Power, King (7). The team then discussed the clinical and contextual significance of potential factors and constructed a list of adolescent and caregiver characteristics and proxies of socio-economic status to explore for relationship to adolescent HRQoL. Bivariate analysis using Spearman’s correlation was then conducted to determine the relationship between each CPQoL-Teens dimension and the selected variables; correlations were considered small (≤0.49), medium (0.50 to 0.79), and large (≥0.80) (28). Variables with statistically significant correlations (i.e. bivariate analysis, p<0.05) were entered into each model order of clinical significance. Assumptions of linearity, homoscedasticity and normality were assessed through examination of Q-Q plots and Shapiro-Wilks; independence of observations assessed with Durbin-Watson statistic, and Multicollinearity assessed through correlation, tolerance and variance inflation factor (VIF) coefficients. No adjustment was made for multiple testing due to the investigative nature of the study. All statistical analysis was conducted using SPSS version 24 (IBM Armonk, NY, USA). A p value of <0.05 was considered significant.