The spasticity-related quality of life 6-dimensions instrument in upper-limb spasticity: Part I Development and responsiveness

Objective

To describe the development of the Spasticity-related Quality of Life 6-Dimensions instrument (SQoL-6D) and its sensitivity to clinical change (responsiveness).

Design

Multicentre, prospective, longitudinal cohort study at 8 UK sites (NCT03442660).

Patients

Adults (n = 104) undergoing focal treatment of upper limb spasticity.

Methods

No condition-specific health-related quality of life tool is available for upper-limb spasticity of any aetiology. The SQoL-6D was developed to fulfil this need, designed to complement the Upper Limb Spasticity Index (which incorporates the Goal Attainment Scaling evaluation of upper limb spasticity [GASeous] tool) with targeted standardised measures. The 6 dimensions of the SQoL-6D (score range 0–4) map onto common treatment goal areas identified in upper-limb spasticity studies. A Total score (0–100) provides overall spasticity-related health status. To assess responsiveness, the SQoL-6D, Global Assessment of Benefit scale and ”GASeous” were administered at enrolment and 8 weeks.

Results

Significant differences in mean SQoL-6D Total score change and effect sizes across patients rating ”some benefit” (0.51) and ”great benefit” (0.88) supported responsiveness.

Conclusion

The SQoL-6D is a promising new measure of health status in upper limb spasticity, that enables systematic assessment of the impact of this condition in relation to patients’ priority treatment goals. A psychometric evaluation of SQoL-6D is presented separately.

The spasticity-related quality of life 6-dimensions instrument in upper-limb spasticity: Part II A first psychometric evaluation

Objective

Psychometric evaluation of the Spasticity- related Quality of Life 6-Dimensions instrument (SQoL-6D).

Design

A clinimetric evaluation conducted in a multicentre, prospective, longitudinal cohort study at 8 UK sites.

Patients

Adult patients (n = 104) undergoing focal treatment of upper-limb spasticity.

Methods

The SQoL-6D was administered in the clinic at enrolment and at 8 weeks, then 1–4 days later at home to assess test-retest reliability.

Results

The SQoL-6D demonstrated adequate construct validity and unidimensionality of the scale, allowing the calculation of a Total score. Cronbach’s alpha (0.74) supported the internal consistency reliability, while the intraclass correlation coefficient supported test-retest reliability (0.82). Correlation coefficients with established instruments supported convergent validity, while significant differences between known-groups (of differing clinical severity) in SQoL-6D Total score confirmed its sensitivity to both cross-sectional and longitudinal differences.

Conclusion

The SQoL-6D is a promising new measure to assess health status for patients with upper-limb spasticity of any aetiology. Further investigation and exploration of the allocation of weights to convert the SQoL-6D to a health-related quality of life utility index, are required.

Development and validation of the Patient Assessment of Constipation Quality of Life questionnaire

OBJECTIVE

Chronic constipation is characterized by difficult, infrequent, or seemingly incomplete bowel movements. The Patient Assessment of Constipation Quality of Life (PAC-QOL) questionnaire was developed to address the need for a standardized, patient-reported outcomes measure to evaluate constipation over time.

MATERIAL AND METHODS

Items for the PAC-QOL were generated from the literature, clinical experts, and patients. Following principal components and multi-trait analyses, 28 items were retained forming four subscales (worries and concerns, physical discomfort, psychosocial discomfort, and satisfaction) and an overall scale. Validation studies were conducted in the United States, Europe, Canada, and Australia, to evaluate the internal consistency reliability (Cronbach's alpha), reproducibility (Intraclass Correlation Coefficients (ICCs)), validity (analysis of variance models), and responsiveness (effect size) of the PAC-QOL scales.

RESULTS

The PAC-QOL scales were internally consistent (Cronbach's alpha >0.80) and reproducible (ICCs >0.70, except for the satisfaction subscale ICC=0.66). PAC-QOL scale scores were significantly associated with abdominal pain (p<0.001) and constipation severity (p<0.05). Effect sizes in patients reporting improvements in constipation over a 6-week period were moderate to large, with subscale effect sizes ranging from 0.76 to 3.41 and the overall scale effect size=1.77. Similar findings were observed in validation studies conducted in Europe, Canada, and Australia.

CONCLUSIONS

The PAC-QOL is a brief but comprehensive assessment of the burden of constipation on patients' everyday functioning and well-being. Multinational studies demonstrate that the PAC-QOL is internally consistent, reproducible, valid, and responsive to improvements over time.

Responsiveness and interpretation of a symptom severity index specific to upper gastrointestinal disorders

BACKGROUND AND AIMS

Determining clinically meaningful change of patient-reported outcome measures is important for evaluating effectiveness of treatments for gastrointestinal (GI) diseases. This study evaluates responsiveness of the Patient Assessment of Gastrointestinal Disorders-Symptom Severity Index (PAGI-SYM) in gastroesophageal reflux disease (GERD) and dyspepsia.

METHODS

The PAGI-SYM was based on a review of the published literature and interviews with patients and clinicians. Items were developed to be linguistically and culturally appropriate for multicountry studies. The PAGI-SYM includes 6 subscales: heartburn/regurgitation, fullness/early satiety, nausea/vomiting, bloating, upper abdominal pain, and lower abdominal pain. Subjects with GERD (n = 810) or dyspepsia (n = 767) participated in this multicountry, observational study. All subjects completed the PAGI-SYM, a global symptom relief questionnaire, and a measure of patient-rated change in GI-related symptoms, the Overall Treatment Effect (OTE) scale. Responsiveness was evaluated at 8 weeks by comparing groups by disease, symptom relief, and OTE (improved, stable, and worsened).

RESULTS

Subjects reporting symptom relief reported significantly lower (better) PAGI-SYM scores than those reporting no symptom relief ( P < 0.0001 to P < 0.0005). Subjects with improvements in overall GI symptoms exhibited significant decreases in PAGI-SYM subscale scores compared with those who remained the same or worsened (all P values < 0.0001). Effect sizes ranged from 0.21-1.28, and standard errors of measurement ranged from 0.29-0.63, depending on subscale and disease sample.

CONCLUSIONS

The PAGI-SYM is a brief symptom severity instrument that measures common GI symptoms. Results suggest that the PAGI-SYM is responsive and sensitive to change in clinical status in subjects with GERD or dyspepsia.

Responsiveness and interpretation of a quality of life questionnaire specific to upper gastrointestinal disorders

BACKGROUND AND AIMS

The Patient Assessment of Upper Gastrointestinal Disorders-Quality of Life (PAGI-QOL) has been developed and validated to assess quality of life in gastroesophageal reflux disease, dyspepsia, and gastroparesis. The aim of this work was to assess responsiveness of the PAGI-QOL to clinical changes and provide guidance for the interpretation of score changes.

METHODS

The analysis was based on 2 observational multicenter, longitudinal, 8-week observation studies, one in the United States and one in 5 European countries. The Overall Treatment Effect scale completed by patients and clinicians at 8 weeks was used to define groups of improved, worsened, and stable patients. Responsiveness was assessed by describing the change in PAGI-QOL scores for each of these groups, comparing these changes over time, and calculating effect sizes and standardized response means. These data were used to define the minimal clinically important difference.

RESULTS

A total of 1736 patients with upper gastrointestinal disorders were analyzed. High sensitivity to change over time was demonstrated, with effect sizes and standardized response means in improved patients for the PAGI-QOL total score ranging from 0.79-1.41. A change of 0.4 for the PAGI-QOL total score might be considered as the minimal clinically important difference when comparing pretreatment and post-treatment PAGI-QOL total scores.

CONCLUSIONS

The PAGI-QOL questionnaire is a responsive and clinically relevant instrument for assessing quality of life in patients with upper gastrointestinal disorders.