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Development of a Modified Psoriatic Arthritis Disease Activity Score Using the Medical Outcomes Study Short Form 12 as a Measure of Quality of Life

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Arthritis Care & Research
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Anthony V Perruccio at University of Toronto
Anthony V Perruccio
Matthew Got
Matthew Got
Matthew Got
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Suzanne Li
Suzanne Li
Suzanne Li
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Yang Ye
Yang Ye
Yang Ye
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Abstract and Figures

Objective The Psoriatic Arthritis Disease Activity Score (PASDAS) is a composite measure of psoriatic arthritis (PsA) disease activity. The length of its patient‐reported components raises concern about questionnaire burden. The PASDAS includes the Medical Outcomes Study Short Form 36 (SF‐36) health survey. We undertook this study to investigate the agreement between the PASDAS and a modified PASDAS (mPASDAS), which substituted the SF‐36 with the shortened SF‐12. Methods A total of 100 patients who fulfilled the criteria of the Classification of Psoriatic Arthritis Study Group for PsA were consecutively recruited. All of the PASDAS‐required variables were collected. The 12 item responses for SF‐12 were extracted from the SF‐36 questionnaire. The PASDAS and the mPASDAS were calculated using the SF‐36 and SF‐12 scores, respectively. A Bland‐Altman plot of the mean differences in PASDAS and mPASDAS scores was generated to evaluate agreement. Construct validity was assessed by examining correlations of the PASDAS and the mPASDAS with the Health Assessment Questionnaire, the Functional Assessment of Chronic Illness Therapy–Fatigue subscale, the EuroQol 5‐domain instrument (health‐related quality of life), and pain scores (range 0–10, visual analog scale). The kappa statistic was used to measure agreement between disease activity states as determined by the PASDAS and mPASDAS. Results The mean ± SD PASDAS and mPASDAS was 3.29 ± 1.39 and 3.24 ± 1.27, respectively. The correlation between the 2 scores was 0.998 (P < 0.0001), and the mean difference was –0.05 (95% confidence interval [95% CI] –0.07, –0.03). Construct validity was found, with nearly identical correlations of the PASDAS and mPASDAS with each of the external health measures. The misclassification rate with the mPASDAS was only 6%. The weighted κ = 0.90 (95% CI 0.82, 0.97). Conclusion The mPASDAS may replace the PASDAS in disease activity assessment given the excellent agreement, validity, and low misclassification rate.
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577
Arthritis Care & Research
Vol. 72, No. 4, April 2020, pp 577–582
DOI 10.1002/acr.23876
© 2019, American College of Rheumatology
Development of a Modied Psoriatic Arthritis Disease
Activity Score Using the Medical Outcomes Study Short
Form 12 as a Measure of Quality of Life
Anthony V.Perruccio,1 MatthewGot,1 SuzanneLi,2 YangYe,2 Dafna D.Gladman,1 and VinodChandran1
Objective. The Psoriatic Arthritis Disease Activity Score (PASDAS) is a composite measure of psoriatic arthritis
(PsA) disease activity. The length of its patient- reported components raises concern about questionnaire burden.
The PASDAS includes the Medical Outcomes Study Short Form 36 (SF- 36) health survey. We undertook this study to
investigate the agreement between the PASDAS and a modied PASDAS (mPASDAS), which substituted the SF- 36
with the shortened SF- 12.
Methods. A total of 100 patients who fullled the criteria of the Classication of Psoriatic Arthritis Study Group
for PsA were consecutively recruited. All of the PASDAS- required variables were collected. The 12 item responses
for SF- 12 were extracted from the SF- 36 questionnaire. The PASDAS and the mPASDAS were calculated using the
SF- 36 and SF- 12 scores, respectively. A Bland- Altman plot of the mean differences in PASDAS and mPASDAS
scores was generated to evaluate agreement. Construct validity was assessed by examining correlations of the
PASDAS and the mPASDAS with the Health Assessment Questionnaire, the Functional Assessment of Chronic Illness
Therapy–Fatigue subscale, the EuroQol 5- domain instrument (health- related quality of life), and pain scores (range
0–10, visual analog scale). The kappa statistic was used to measure agreement between disease activity states as
determined by the PASDAS and mPASDAS.
Results. The mean ± SD PASDAS and mPASDAS was 3.29 ± 1.39 and 3.24 ± 1.27, respectively. The correlation
between the 2 scores was 0.998 (P < 0.0001), and the mean difference was –0.05 (95% condence interval [95%
CI] –0.07, –0.03). Construct validity was found, with nearly identical correlations of the PASDAS and mPASDAS with
each of the external health measures. The misclassication rate with the mPASDAS was only 6%. The weighted
κ = 0.90 (95% CI 0.82, 0.97).
Conclusion. The mPASDAS may replace the PASDAS in disease activity assessment given the excellent
agreement, validity, and low misclassication rate.
INTRODUCTION
Psoriatic arthritis (PsA) is an inammatory arthritis that is
associated with psoriasis (1). The varied manifestations of PsA
include peripheral arthritis, enthesitis, dactylitis, axial arthritis, and
psoriatic skin and nail involvement (2,3). PsA is associated with
pain, physical function limitations, and decreased quality of life.
Studies have established the importance of composite disease
activity measures for assessment of disease activity in PsA (4–6),
which can provide a quick summary of current disease activity
and assist in dening high and low disease activity, establishing
response criteria, and treating to target (7).
The Psoriatic Arthritis Disease Activity Score (PASDAS) is
a composite disease activity measure (range 0–10) that was
developed by the Group for Research and Assessment of
Psoriasis and Psoriatic Arthritis (GRAPPA) Composite Exercise
(GRACE project) for use in randomized controlled trials (6). The
PASDAS captures many of the clinical features of PsA, including
The Psoriatic Arthritis Program is supported by the Krembil Foundation.
Dr. Got’s work was supported by a Canadian Rheumatology Association
Research Summer Studentship.
1Anthony V. Perruccio, PhD, Matthew Got, MD, Dafna D. Gladman, MD,
FRCPC, Vinod Chandran, MBBS, MD, DM, PhD: University of Toronto and the
Krembil Research Institute, University Health Network, Toronto, Ontario,
Canada; 2Suzanne Li, MMath, Yang Ye, MMath: Krembil Research Institute,
University Health Network, Toronto, Ontario, Canada.
Drs. Perruccio and Got contributed equally to this work.
No potential conicts of interest relevant to this article were
reported.
Address correspondence to Vinod Chandran, MBBS, MD, DM, PhD,
Psoriatic Arthritis Program, Centre for Prognosis Studies in the Rheumatic
Diseases, Krembil Research Institute, University Health Network, 399 Bathurst
Street 1E-410B, Toronto, Ontario, Canada, M5T 2S8. E-mail: vinod.chandran@
uhnresearch.ca.
Submitted for publication January 22, 2019; accepted in revised form
March 5, 2019.
... Finally, quality of life was measured by selfreport. Although, the SF-12 questionnaires has been validated and extensively used, self-reported tools are difficult to avoid social desirability bias and may overestimate true condition (43). As such, after exposure to a home-based BP monitoring device that very clearly encouraged adherence, intervention group participants may have been more likely to report higher level life quality without actually changing their physical or mental health condition. ...
Effectiveness of a mHealth intervention on hypertension control in a low-resource rural setting: A randomized clinical trial
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Background Despite the increasing popularity of mHealth, little evidence indicates that they can improve health outcomes. Mobile health interventions (mHealth) have been shown as an attractive approach for health-care systems with limited resources. To determine whether mHealth would reduce blood pressure, promote weight loss, and improve hypertension compliance, self-efficacy and life quality in individuals with hypertension living in low-resource rural settings in Hubei, China. Methods In this parallel-group, randomized controlled trial, we recruited individuals from health-care centers, home visits, and community centers in low-resource rural settings in Hubei, China. Of 200 participants who were screened, 148 completed consent, met inclusion criteria, and were randomly assigned in a ratio of 1:1 to control or intervention. Intervention group participants were instructed to use the Monitoring Wearable Device and download a Smartphone Application, which includes reminder alerts, adherence reports, medical instruction and optional family support. Changes in the index of Cardiovascular health risk factors from baseline to end of follow-up. Secondary outcomes were change in hypertension compliance, self-efficacy and life quality at 12 weeks. Results Participants (n = 134; 66 in the intervention group and 68 controls) had a mean age of 61.73 years, 61.94% were male. After 12 weeks, the mean (SD) systolic blood pressure decreased by 8.52 (19.73) mm Hg in the intervention group and by 1.25 (12.47) mm Hg in the control group (between-group difference, −7.265 mm Hg; 95% CI, −12.89 to −1.64 mm Hg; P = 0.012), While, there was no difference in the change in diastolic blood pressure between the two groups (between-group difference, −0.41 mm Hg; 95% CI, −3.56 to 2.74 mm Hg; P = 0.797). After 12 weeks of follow-up, the mean (SD) hypertension compliance increased by 7.35 (7.31) in the intervention group and by 3.01 (4.92) in the control group (between-group difference, 4.334; 95% CI, 2.21 to −6.46; P < 0.01), the mean (SD) hypertension compliance increased by 12.89 (11.95) in the intervention group and by 5.43 (10.54) in the control group (between-group difference, 7.47; 95% CI, 3.62 to 11.31; P < 0.01), the mean (SD) physical health increased by 12.21 (10.77) in the intervention group and by 1.54 (7.18) in the control group (between-group difference, 10.66; 95% CI, 7.54–13.78; P < 0.01), the mean (SD) mental health increased by 13.17 (9.25) in the intervention group and by 2.55 (5.99) in the control group (between-group difference, 10.93; 95% CI, 7.74 to 14.12; P < 0.01). Conclusions Among participants with uncontrolled hypertension, individuals randomized to use a monitoring wearable device with a smartphone application had a significant improvement in self-reported hypertension compliance, self-efficacy, life quality, weight loss and diastolic blood pressure, but no change in systolic blood pressure compared with controls.
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... The PASDAS was calculated using a previously reported formula [11], although the original SF-36 physical component score was substituted for the physical component score of the SF-12 as a more reliable alternative [12]. ...
Defining the minimal important change (MIC) and meaningful change value (MCV) of the Psoriatic Arthritis Disease Activity Score (PASDAS) in a routine practice cohort of Psoriatic Arthritis patients
Article
Full-text available
  • Jan 2022
OBJECTIVE To determine the Minimal Important Change (MIC) values and Meaningful Change Values (MCV) of the Psoriatic Arthritis Disease Activity Score (PASDAS) and the Standard Error of Measurement (SEM) of the PASDAS. METHODS Routine practice data of 544 patients with Psoriatic Arthritis (PsA) was available for analysis. An anchor-based method using linear regression analyses was used to determine the MICs and MCVs of the PASDAS. With this anchor-based method we compared changes in PASDAS score with an external reference (anchor). The anchor question inquired whether the patient’s wellbeing had changed since their previous visit. It consisted of a 7-point Likert scale (range: very much improved to very much deteriorated). Interperiod correlation matrix analysis was performed to determine the SEM. RESULTS The overall MIC and MCV of the PASDAS were 0.67 (95% CI; 0.55–0.79) and 1.34 (95% CI; 1.21–1.46), respectively. Results for improvement and deterioration were 0.65 (95% CI; 0.46–0.83) and 0.71 (95% CI; 0.49–0.93) for the MIC, respectively, and 1.29 (95% CI; 1.11–1.48) and 1.42 (95% CI; 1.19–1.64) for the MCV, respectively. The SEM was determined at 0.81. CONCLUSIONS The MIC of the PASDAS provides an extra tool for physicians in the treatment of PsA patients to put context to the patient’s perspective of disease activity, while the MCV might aid the use of the PASDAS in PsA clinical trials.
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... QOL was measured with the Chinese version of the Medical Outcomes Study Short Form 12 (SF-12) (Zhang et al., 2011;Perruccio et al., 2020). The SF-12 is a generic instrument with 12 items addressing eight health domains: physical functioning, role limitations due to physical problems, bodily pain, vitality, and social functioning as well as role limitations each related to emotional problems and mental health. ...
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Objective This study aimed to describe the one-month prevalence of insomnia symptoms (insomnia hereafter) and the demographic and clinical correlates, and its association with quality of life (QOL) in Chinese patients with HBV-related liver disease. Method A total of 689 patients with HBV-related liver disease in Beijing, China formed the study sample. Three forms of insomnia including difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS) and early morning awakening (EMA) were assessed using standardized questions. QOL was measured using the Medical Outcomes Study Short Form 12 (SF-12). Results The one-month prevalence of at least one type of insomnia was 69.5%, while DIS, DMS and EMA were 60.4%, 54.7% and 50.9%, respectively. Only 4.8% of patients suffering from insomnia received treatment. Multiple logistic regression analyses revealed that pre-existing medical conditions were positively associated with DIS and EMA; patients with more severe depressive symptoms were more likely to have DIS, DMS and EMA; local residents were less likely to have DIS; and those who were married and older were more likely to have DMS. Insomnia was not independently associated with QOL. Conclusions Insomnia is common in Chinese patients with HBV-related liver disease with a very low rate of treatment. Greater attention should be given to identify and treat insomnia in this patient population.
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... where CRP is in milligrams per litre (mg/l), the global (disease activity) VAS scores range between 0 and 100 mm, the SF12-PCS ranges between 0 and 100, and the maximum scores for the TJC, SJC, LEI and dactylitis are 68, 66, 6 and 20, respectively. The original PASDAS was developed using the SF-36 instead of the SF-12, but as research has indicated that using the SF12 does not alter the results of the PASDAS and helps to lower patient burden, we chose to use the SF-12 [18,19]. ...
Measuring disease activity in psoriatic arthritis: PASDAS implementation in a tightly monitored cohort reveals residual disease burden
Article
Full-text available
  • Dec 2020
Objectives We aimed to investigate the disease activity and overall disease burden of (subgroups of) patients with PsA using the Psoriatic Arthritis Disease Activity Score (PASDAS) in an already tightly monitored cohort. Methods This is a cross-sectional study evaluating data from the first visit of 855 PsA patients after implementation of the PASDAS in our tightly monitored cohort [e.g. DAS 28 (DAS28) was provided as an anchor]. Differences in clinical outcomes between subgroups of patients using established cut-offs for disease activity status [i.e. very low (VLDA), low (LDA), moderate (MDA), and high disease activity (HDA)] were examined. Results Based on the PASDAS, 53.1% of patients were in VLDA/LDA. 29.5% of patients had ≥1 swollen joint, 20.6% had ≥1 enthesitis index point and 3.0% had active dactylitis. Based on DAS28, 77.5% of the patients were in VLDA/LDA. Patients reaching both DAS28 VLDA/LDA status and PASDAS VLDA/LDA status [N = 445 (52.0%)] were compared with patients reaching only DAS28 VLDA/LDA status [N = 218 (25.5%)]. For these latter patients, significantly worse scores on separate parameters were found in measures used for PASDAS/DAS28 calculation (e.g. swollen and tender joint count and patient’s visual analogue scale global disease activity) as well as other disease measures (e.g. function and inflammatory back pain). This result remained, even when the stricter VLDA cut-off was used for the DAS28. Conclusion PASDAS implementation uncovered relevant residual disease activity in a quarter of patients previously assessed as being in DAS28 VLDA/LDA, underscoring the potential value of PASDAS measurements in PsA clinical care.
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... All strains confer with safety certificates recognized by the European Food Safety Authority. Medical history, clinical examinations, evaluation of disease activity by modified psoriatic arthritis disease activity score (mPASDAS) [13,14], blood and stool samples were obtained at baseline, after 12 and 24 weeks. Telephone interviews were performed after 6 weeks to ensure compliance and identify potential adverse events. ...
Effects of Probiotic Strains on Disease Activity and Enteric Permeability in Psoriatic Arthritis–A Pilot Open-Label Study
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(1) Background: Psoriatic Arthritis (PsA) is a painful disease of the joints and spine. Recent reports observed distinct enteric dysbiosis in PsA; intake of probiotic strains is considered to ameliorate enteric dysbiosis. If probiotics are effective in PsA is elusive. (2) Methods: In this pilot open-label study we enrolled 10 PsA patients with low to medium disease activity who received probiotics for 12 weeks. Analysis of faecal zonulin, α1-antitrypsin and calprotectin, as well as peripheral immune phenotyping was performed at baseline, after 12 weeks and 12 weeks after termination of probiotic intake. (3) Results: All patients showed increased levels of the enteric permeability marker zonulin which correlated with the frequency of peripheral Th17 cells. Calprotectin, a marker for intestinal inflammation was elevated in 6 out of 10 patients. Probiotic intake resulted in a reduction of disease activity and gut permeability. These effects, however, were not sustained beyond termination of probiotic intake. (4) Conclusions: PsA patients suffer from enhanced enteric permeability and inflammation. Probiotics may ameliorate disease activity in PsA by targeting these alterations.
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... Apart from 2 studies that evaluated the construct validity of HAQ DI and SF-36 physical functioning (12,13), the validity and responsiveness of different patient-reported outcome mea sures for the assessment of physical function in PsA have not been compared. The SF-12 is a short version of the SF-36 and was recently proposed be a feasible option to replace the SF-36 in scoring a composite measure of disease activity in PsA, giving similar results as the original formula (14). ...
Comparing the Patient‐Reported Physical Function Outcome Measures in a Real‐Life International Cohort of Patients With Psoriatic Arthritis
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Objective We evaluated the psychometric properties of 3 patient‐reported outcome measures to assess the physical function in psoriatic arthritis (PsA). Methods Data were available for the Health Assessment Questionnaire disability index (HAQ DI), the 12‐item Short Form instrument physical component summary (SF‐12 PCS), and the Psoriatic Arthritis Impact of Disease instrument functional capacity score (PsAID‐FC). Data came from a longitudinal study in 14 countries of consecutive adults with definite PsA with ≥2 years of duration. The score distribution, construct validity, responsiveness, and thresholds of meaning of the patient‐reported outcome measures were evaluated. Results At baseline, 414 subjects (52% male) were analyzed. The mean ± SD age was 52.4 ± 12.5 years and duration of illness was 10.9 ± 8.1 years. Ceiling effects were noted in 31% and 21% of patients for HAQ DI and PsAID‐FC, respectively; floor effects were minimal. All 3 patient‐reported outcome measures met a priori hypotheses for construct validity. After a median follow‐up of 4.1 (interquartile range 2.7) months in 350 patients, 27%, 54%, and 18% of patients reported themselves improved, not changed, and worsened, respectively. Change scores were statistically different for groups for worsening versus no‐change for all patient‐reported outcome measures. PsAID‐FC was more sensitive to change than the other 2 patient‐reported outcome measures. Comparing groups with worsening condition to no‐change, the standardized response mean square ratios were HAQ DI 29.9, SF‐12 PCS 16.7, and PsAID‐FC 40.1. Conclusion HAQ DI, SF‐12 PCS, and PsAID‐FC are valid measures of physical function for PsA. PsAID‐FC, a single question, performed similarly to the other patient‐reported outcome measures and may be an additional option to measure PsA‐specific physical function.
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Non response, incomplete and inconsistent responses to self-administered health-related quality of life measures in the general population: patterns, determinants and impact on the validity of estimates. A population-based study in France using the MOS SF-36
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Background Health-related quality of life (HRQoL) measures are increasingly used in the general population. However, little is known about patterns and determinants of unanswered or unusable questionnaires and their consequences on estimates of HRQoL. Methods The 2003 Decennial Health Survey collected socio-demographic and health information, including HRQoL, for 30,782 adults representative of the French population. The pattern, determinants and impact on estimate validity of non, incomplete and inconsistent responses to the SF-36 questionnaire were determined. For this, phi coefficients, polytomous logistic regression models and multiple imputation methods were used. Results Only 48% of the subjects eligible for the HRQoL measurement provided a complete and consistent SF-36 questionnaire. Three patterns of non-response and five of partial (incomplete or inconsistent) response were identified, sharing largely similar socio-demographic profiles (higher age, lower educational level and economic status, foreign background, and isolated). The consequences of non and partial responses on HRQoL estimates were large in several groups of subjects although these biases ran in opposite directions and partially neutralized each other. Conclusions When measuring HRQoL in the general population, missing and inconsistent data are frequent, especially in elderly, educationally and socio-economically deprived, foreign and isolated groups. Methods for handling missing data are required to correct for potentially the associated and serious selection and non-differential information biases in studies targeting or investigating these groups.
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Objective: To develop new composite disease activity indices for psoriatic arthritis (PsA). Methods: Data from routine clinic visits at multiple centres were collected in a systematic manner. Data included all domains identified as important in randomised controlled trials in PsA. Decisions to change treatment were used as surrogates for high disease activity. New indices were developed by multiple linear regression (psoriatic arthritis disease activity score: PASDAS) and empirically, utilising physician-defined cut-offs for disease activity (arithmetic mean of desirability functions: AMDF). These were compared with existing composite measures: Composite Psoriatic arthritis Disease Activity Index (CPDAI), Disease Activity for PSoriatic Arthritis (DAPSA), and Disease Activity Score for rheumatoid arthritis (DAS28). Results: 161/503 (32%) subjects had treatment changes. Although all measures performed well, compared with existing indices, PASDAS was better able to discriminate between high and low disease activity (area under receiver operating curves (ROC)) curve with 95% CI: PASDAS 0.773 (0.723, 0.822); AMDF 0.730 (0.680, 0.780); CPDAI 0.719 (0.668, 0.770); DAPSA 0.710 (0.654, 0.766); DAS28 0.736 (0.680, 0.792). All measures were able to discriminate between disease activity states in patients with oligoarthritis, although area under the receiver operating curves (AUC) were generally smaller. In patients with severe skin disease (psoriasis area and severity index>10) both nonparametric and AUC curve statistics were nonsignificant for all measures. Conclusions: Two new composite measures to assess disease activity in PsA have been developed. Further testing in other datasets, including comparison with existing measures, is required to validate these instruments.
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Psoriatic arthritis is a complex heterogeneous disease manifesting with skin disease and a number of musculoskeletal abnormalities including arthritis, enthesitis, dactylitis and spondylitis. While not all of these manifestations are present in every patient, assessment of disease activity should account for these domains. To combine these domains into one composite score has been challenging but several have been developed. The Psoriatic Arthritis Disease Activity Score (PASDAS) was developed as part of an international Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) exercise.1 This measure includes physician-reported and patient-reported outcome measures combined into a composite index. The PASDAS requires the patient to complete a visual analogue scale and the short form 36 (SF36). The latter consists of 36 questions covering domains of physical and mental health. A shorter, 12 …
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The management of psoriatic arthritis (PsA) and psoriasis has undergone major advancements over the last decade. This has been made possible, in part, due to the introduction of new therapies for their management, as well as global collaboration in the development of outcome measures and "treat- to- target" paradigms. In this review article, we discuss how disease activity is measured and the outcome measures that have been recently developed for the management of PsA. The importance of assessing the individual domains as well as global assessments both from the physician and patient perspective, and the development of composite measures are discussed. The newer PsA specific measures are expected to be more commonly used in clinical trials as well as clinical practice.
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Short-Form 12 or Short-Form 36 to measure quality-of-life changes in dialysis patients?
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Short-Form 36 (SF-36) is a self-report health-related quality-of-life (HRQOL) questionnaire, widely used in dialysis patients. It consists of physical and mental component scores (PCS/MCS), ranging from 0 to 100. To improve efficiency, the Short-Form 12 (SF-12) was developed to reproduce PCS and MCS. We assessed the ability of SF-12 versus SF-36 to detect change over time, and the association of SF-12 versus SF-36 with short-term and long-term mortality in dialysis patients. Patients were selected from the Netherlands Cooperative Study on the Adequacy of Dialysis (N = 1379), a prospective follow-up study among incident dialysis patients (62.1% HD) who completed SF-36 measurements every 6 months. Changes in scores of SF-12 versus SF-36 were compared with intra-class correlation coefficients (ICCs). Subsequently, Bland-Altman plots were used to assess limits of agreement. Relationship with mortality was assessed with Cox models with and without a time-dependent variable, adjusted for age, sex, ethnicity, comorbidity and dialysis modality at baseline. ICC for change in scores was 0.90 for MCS and 0.84 for PCS. Mean difference was -0.1 and 0.2, respectively, and limits of agreement were -8.3 to 8.4 for MCS change in scores and -8.8 to 9.2 for PCS. Adjusted hazard ratio's for mortality per 5 units increment were 0.87 (95% CI: 0.84-0.91) for MCS12, 0.87 (95% CI: 0.84-0.90) for MCS36, 0.79 (95% CI: 0.76-0.83) for PCS12 and 0.75 (95% CI: 0.71-0.78) for PCS36. SF-12 can be used to detect change in HRQOL in cohort studies on dialysis patients. SF-12 and SF-36 were similarly associated with short-term and long-term mortality. However, the wide limits of agreement indicate that SF-12 and SF-36 can give different scores on the individual level, suggesting that for individual purposes SF-36 instead of SF-12 should be used. © The Author 2015. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.
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Composite Disease Activity and Responder Indices for Psoriatic Arthritis: A Report from the GRAPPA 2013 Meeting on Development of Cutoffs for Both Disease Activity States and Response
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Objective: There are several new composite indices for assessing disease activity in psoriatic arthritis (PsA). Each may function as a disease state variable and a responder index. The aim of our study was to determine cutoffs for disease activity and response. Methods: Data from the Group for GRAPPA Composite Exercise (GRACE) study were used to develop cutoffs using a number of different approaches. Voting on choice of cutoff was undertaken at the 2013 GRAPPA Annual Meeting in Toronto, Ontario, Canada. Results: After voting, results for cutoffs for low/high disease activity for the Psoriatic ArthritiS Disease Activity Score (PASDAS), GRAppa Composite scorE (GRACE index), and Composite Psoriatic Disease Activity Index (CPDAI), respectively, were 3.2/5.4, 2.3/4.7, and 4/8. The measurement error for each composite score was estimated at 0.8, 1, and 2 for PASDAS, GRACE, and CPDAI, respectively. Conclusion: Response criteria for the new composite indices have been developed. These now require further validation and testing in other datasets.
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This module reflected work within the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA) to develop and validate composite disease activity measures in psoriatic arthritis (PsA). At the Outcome Measures in Rheumatology (OMERACT) 8 Meeting, a core set of domains to be assessed in randomized controlled trials (RCT) and longitudinal observational studies of PsA was agreed upon. At OMERACT 10, 5 proposed composite responder definitions for PsA were reviewed and discussed, including new data from the GRACE (GRAppa Composite Exercise) study. At OMERACT 11, ongoing retrospective analyses of RCT data using the 3 proposed measures (Composite Psoriatic Disease Activity Index, Psoriatic Arthritis Disease Activity Score, and Arithmetic Mean of the Desirability Function) were discussed in detail. There was agreement that developing composite outcome measures for use in RCT and longitudinal observational studies in PsA was important. Concerns were expressed regarding development of a single measure that encompassed diverse domains, such as joint counts, quality of life (QOL), and disability measures. It was emphasized that the use of any composite measure should include the ability to differentiate between activity in individual domains, such as enthesitis or psoriasis, such that the effect of each could be assessed independently. It was also agreed that patients would be systematically involved in further development and refinement of composite measures. Future plans include qualitative work with patients to explore their experience of disease activity and statistical modeling to explore how each of the proposed measures will perform in different disease subgroups.
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Article
  • May 2014
Objective: To compare the performance of the Psoriatic Arthritis Disease Activity Score (PASDAS), the Arithmetic Mean of the Desirability Function (AMDF), the Composite Psoriatic Disease Activity Index (CPDAI), and the Disease Activity Index for Psoriatic Arthritis (DAPSA) in the GO-REVEAL data set. The Disease Activity Score using 28 joints (DAS28) was used as a comparator. Methods: The GO-REVEAL study did not allow full computation of all the composite scores (a modified version of CPDAI was used). The performance of the scores at baseline and followup (weeks 14 and 24) was compared using effect sizes. Results: All indices could distinguish response to treatment at 14 and 24 weeks. Effect sizes at 24 weeks for the 50 mg (100 mg) golimumab doses were 2.18 (2.36), 2.08 (2.36), 1.09 (1.41), 1.80 (1.78), and 1.13 (1.18) for PASDAS, AMDF, modified CPDAI, DAS28, and DAPSA, respectively. Comparison of 24-week values across the 3 treatment groups (placebo, golimumab 50 mg, and golimumab 100 mg) by an analysis of covariance using the baseline values as covariates gave the following F statistics: PASDAS 18.3, AMDF 19.6, modified CPDAI 9.4, DAS28 13.6, and DAPSA 7.9; all of these are highly significant. When the analysis was confined to the 2 golimumab treatment groups, there were no significant between-treatment group differences with any of the composite measures. Conclusion: PASDAS and AMDF were better able to distinguish treatment effect, having larger effect sizes at 24 weeks. PASDAS, AMDF, and modified CPDAI better reflected domains such as skin, enthesitis, and dactylitis.
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Adult measures of general health and health-related quality of life: Medical Outcomes Study Short Form 36-item (SF-36) and Short Form 12-item (SF-12) Health Surveys, Nottingham Health Profile (NHP), Sickness Impact Profile (SIP), Medical Outcomes Study Short Form 6D (SF-6D), Health Utilities Index Mark 3 (HUI3), Quality of Well-Being Scale (QWB), and Assessment of Quality of Life (AQoL)
Article
  • Nov 2011
Scores on the SF-36 and SF-12 scales range from 0–100, with higher scores indicating better health. On the physical functioning scale, low scores are typical of someone who experiences many limitations in physical activities, including bathing or dressing, while high scores represent someone who is able to perform these types of activities without limitations. Low scores on the role physical scale represent someone who experiences many limitations in work or other daily activities, and high scores characterize someone who has no difficulties with these activities. Low scores on the social functioning typify a person who experiences a great deal of difficulties in normal social activities due to physical and emotional health problems, and high scores represent someone who is able to perform normal social activities without interference due to physical or emotional health. Low scores on the bodily pain scale are typical of a person who has very severe and extremely limiting pain, and high scores represent individuals who have no pain or pain-related limitations. On the mental health scale, low scores represent high levels of nervousness and depression, while high scores characterize someone who feels peaceful, happy, and calm. Low scores on the role emotional scale represent someone who experiences many problems with work or other daily activities as a result of emotional ill health, and high scores represent those who have no problems with work or other daily activities as a result of emotional health. On the vitality scale, low scores are typical of someone who feels tired and worn out all of the time, while high scores characterize those who feel full of pep and energy. Low scores on the general health scale represent a person who believes their health to be poor and likely to get worse, and high scores represent someone who sees their health as excellent (1).
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