Patient reports of health outcome for adults living with sickle cell disease: development and testing of the ASCQ-Me item banks

Abstract

BackgroundProviders and patients have called for improved understanding of the health care requirements of adults with sickle cell disease (SCD) and have identified the need for a systematic, reliable and valid method to document the patient-reported outcomes (PRO) of adult SCD care. To address this need, the Adult Sickle Cell Quality of Life Measurement System (ASCQ-Me) was designed to complement the Patient Reported Outcome Measurement Information System (PROMIS®). Here we describe methods and results of the psychometric evaluation of ASCQ-Me item banks (IBs).MethodsAt seven geographically-disbursed clinics within the US, 556 patients responded to questions generated to assess cognitive, emotional, physical and social impacts of SCD. We evaluated the construct validity of the hypothesized domains using exploratory factor analysis (EFA), parallel analysis (PA), and bi-factor analysis (Item Response Theory Graded Response Model, IRT-GRM). We used IRT-GRM and the Wald method to identify bias in responses across gender and age. We used IRT and Cronbach’s alpha coefficient to evaluate the reliability of the IBs and then tested the ability of summary scores based on IRT calibrations to discriminate among tertiles of respondents defined by SCD severity.ResultsOf the original 140 questions tested, we eliminated 48 that either did not form clean factors or provided biased measurement across subgroups defined by age and gender. Via EFA and PA, we identified three subfactors within physical impact: sleep, pain and stiffness impacts. Analysis of the resulting six item sets (sleep, pain, stiffness, cognitive, emotional and social impacts of SCD) supported their essential unidimensionality. With the exception of the cognitive impact IB, these item sets also were highly reliable across a broad range of values and highly significantly related to SCD disease severity.ConclusionASCQ-Me pain, sleep, stiffness, emotional and social SCD impact IBs demonstrated exceptional measurement properties using modern and classical psychometric methods of evaluation. Further development of the cognitive impact IB is required to improve its sensitivity to differences in SCD disease severity. Future research will evaluate the sensitivity of the ASCQ-Me IBs to change in SCD disease severity over time due to health interventions.

Sensitivity of alternative measures of functioning and wellbeing for adults with sickle cell disease: comparison of PROMIS® to ASCQ-Me℠

“…For ASCQ-Me, scores were based on the 556 adults with SCD who participated in the field test [3]. The sociodemographic characteristics of this population were consistent with the sociodemographic characteristics of the adult clinical population who have SCD [78, 79].…”

“…Here we report such a study describing the validity of the Patient-Reported Outcome Measurement Information System (PROMIS®) which was designed to be applicable across chronic diseases [6, 7], as well as one of the condition-specific measures included in the PCAR -- ASCQ-Me℠ [2]. The health assessments in both PROMIS and ASCQ-Me were built and scored using Item Response Theory (IRT), specifically the Graded Response Model (GRM), and both use a web-based, electronic data collection platform [3, 8]. Given that PROMIS was designed to be universally applicable, [9] the value added of a system like ASCQ-Me may be in question.…”

Community Health Workers as Support for Sickle Cell Care

“…The Adult Sickle Cell Quality of Life Measurement Information System (ASQ-ME) question bank was developed specifically for quality of life in SCD, using PROMIS methodology . 95,96 Quality of life in SCD has been reported using the SF-36. 97,98 Unfortunately, behavioral change promoted by CHW does not guarantee quiescent symptoms of SCD, even with complete adherence to care plans.…”

Hemoglobinopathies and Leg Ulcers

“…1,2 Geographic prevalence is variable for major hemoglobinopathies in the different regions of the world; however, the World Health Organization has stressed that hemoglobinopathies are a growing health problem in 71% of countries (mostly low-and middle-income countries). 3,4 These disorders are endemic in the Mediterranean, Africa, and Asia and recognized as the most common rare diseases of genetic origin in Europe. 4 With increasing mobility and migration flows, the prevalence of SCD is significantly growing in many Western countries and as a result makes them a global public health problem.…”

“…4 With increasing mobility and migration flows, the prevalence of SCD is significantly growing in many Western countries and as a result makes them a global public health problem. 3 As an example of the challenge of these types of ulcer, leg ulcers in SCD have a healing rate of 16 times slower than venous leg ulcers and high recurrence rate (97% in less than a year).…”