Exploring preferences for domain-specific goal management in patients with polyarthritis: what to do when an important goal becomes threatened?

Usually priorities in goal management--intended to minimize discrepancies between a given and desired situation--are studied as person characteristics, neglecting possible domain-specific aspects. However, people may make different decisions in different situations depending on the importance of the personal issues at stake. Aim of the present study therefore was to develop arthritis-related vignettes to examine domain-specific goal management and to explore patients' preferences. Based on interviews and literature, situation-specific hypothetical stories were developed in which the main character encounters a problem with a valued goal due to arthritis. Thirty-one patients (61 % female, mean age 60 years) evaluated the face validity of the newly developed vignettes. Secondly, 262 patients (60 % female, mean age 63 years) were asked to come up with possible solutions for the problems with attaining a goal described in a subset of the vignettes. Goal management strategies within the responses and the preference for the various strategies were identified. The 11 developed vignettes in three domains were found to be face-valid. In 90 % of the responses, goal management strategies were identified (31 % goal maintenance, 29 % goal adjustment, 21 % goal disengagement, and 10 % goal re-engagement). Strategy preference was related to domains. Solutions containing goal disengagement were the least preferred. Using vignettes for measuring domain-specific goal management appears as valuable addition to the existing questionnaires. The vignettes can be used to study how patients with arthritis cope with threatened goals in specific domains from a patient's perspective. Domain-specific strategy preference emphasizes the importance of a situation-specific instrument.

Linking physical function outcomes in rheumatology: performance of a crosswalk for converting Health Assessment Questionnaire scores to Short Form 36 physical functioning scale scores.

OBJECTIVE: To evaluate the reliability of a crosswalk, developed in The Netherlands, between the Health Assessment Questionnaire (HAQ) disability index (DI) and the Short Form 36 physical functioning scale (PF-10) in a sample of patients with various rheumatic diseases in the US. METHODS: Baseline data from patients with rheumatoid arthritis (RA; n = 29,020), fibromyalgia (FM; n = 3,776), and systemic lupus erythematosus (SLE; n = 1,609) participating in the National Data Bank for Rheumatic Diseases were analyzed. Reliability of the crosswalk was evaluated by calculating intraclass correlation coefficients (ICCs), and agreement between observed and predicted scores was evaluated using the Bland-Altman approach. RESULTS. The crosswalk produced reliable conversions for both the HAQ DI (ICC range 0.70-0.77) and PF-10 (ICC range 0.73-0.78) in all 3 disease groups. The mean difference between observed and expected scores was close to zero in US patients with RA. For all 3 disease groups, the limits of agreement were fairly wide and conversion at the level of individual patients is not recommended. CONCLUSION: The crosswalk produced reliable conversions at the group level in a crosscultural setting and can be used to convert HAQ DI to PF-10 scores and vice versa in US patients with RA, FM, or SLE.

Development and evaluation of a crosswalk between the SF-36 physical functioning scale and Health Assessment Questionnaire disability index in rheumatoid arthritis.

BACKGROUND: The SF-36 physical functioning scale (PF-10) and the Health Assessment Questionnaire disability index (HAQ-DI) are the most frequently used instruments for measuring self-reported physical function in rheumatoid arthritis (RA). The objective of this study was to develop a crosswalk between scores on the PF-10 and HAQ-DI in RA. METHODS: Item response theory (IRT) methods were used to co-calibrate both scales using data from 1791 RA patients. The appropriateness of a Rasch-based crosswalk was evaluated by comparing it with crosswalks based on a two-parameter and a multi-dimensional IRT model. The accuracy of the final crosswalk was cross-validated using baseline (n = 532) and 6-month follow-up (n = 276) data from an independent cohort of early RA patients. RESULTS: The PF-10 and HAQ-DI adequately fit a unidimensional Rasch model. Both scales measured a wide range of functioning, although the HAQ-DI tended to better target lower levels of functioning. The Rasch-based crosswalk performed similarly to crosswalks based on the two-parameter and multidimensional IRT models. Agreement between predicted and observed scale scores in the cross-validation sample was acceptable for group-level comparisons. The longitudinal validity in discriminating between disease response states was similar between observed and predicted scores. CONCLUSION: The crosswalk developed in this study allows for converting scores from one scale to the other and can be used for group-level analyses in patients with RA.

Need for online information and support of patients with systemic sclerosis.

OBJECTIVE: Interactive health communication applications (IHCAs) offer interesting possibilities to support systemic sclerosis (SSc) patients, since SSc is an uncommon, severe disease that needs a multidisciplinary treatment. This study aimed to investigate patients' needs for a hospital-based IHCA. METHODS: A survey study was conducted among a large sample (n = 429) of SSc patients of the University Medical Centre St. Radboud in Nijmegen, The Netherlands. Patients were asked about their current disease-related internet use, their perceived importance of diverse information topics, and their usefulness of 8 widely used online health services. To examine how disease specific their needs were, the results of SSc patients were compared with the results of a sample of rheumatoid arthritis (RA) patients (n = 1,284). RESULTS: In total, 746 patients (44% of the approached patients) returned a completed questionnaire and fulfilled all of the inclusion criteria. Of them, 569 (76%) had internet access. SSc patients used the internet especially for information (85%), and they expressed a need for information on physical, psychological, and social consequences of the disease. Concerning a hospital-based IHCA, e-consults, information about disease and treatment, and home access to their electronic medical records were perceived as most useful. SSc patients were more positive about the usefulness of the online applications than were RA patients, especially for e-consults and peer support forums. CONCLUSION: It would be valuable to offer SSc patients a hospital-based IHCA, including the online information and support they desire. When taking the needs of patients into account, an IHCA could become a valuable addition to their regular treatment.

Translation and validation of the Dutch version of the Effective Consumer Scale (EC-17).

PURPOSE: The Effective Consumer Scale (EC-17) measures the skills of musculoskeletal patients in managing their own healthcare. The objectives of this study were to translate the EC-17 into Dutch and to further evaluate its psychometric properties. METHODS: The EC-17 was translated and cognitively pretested following cross-cultural adaptation guidelines. Two hundred and thirty-eight outpatients (52 % response rate) with osteoarthritis or fibromyalgia completed the EC-17 along with other validated measures. Three weeks later, 101 patients completed the EC-17 again. RESULTS: Confirmatory factor analysis supported the unidimensional structure of the scale. The items adequately fit the Rasch model and only one item demonstrated differential item functioning. Person reliability was high (0.92), but item difficulty levels tended to cluster around the middle of the scale, and measurement precision was highest for moderate and lower levels of skills. The scale demonstrated adequate test-retest reliability (ICC = 0.71), and correlations with other measures were largely as expected. CONCLUSION: The results supported the validity and reliability of the Dutch version of the EC-17, but suggest that the scale is best targeted at patients with relatively low levels of skills. Future studies should further examine its sensitivity to change in a clinical trial specifically aimed at improving effective consumer skills.

Crosscultural measurement equivalence of the Health Assessment Questionnaire II.

OBJECTIVE: To evaluate the crosscultural measurement equivalence of the US and Dutch Health Assessment Questionnaire II (HAQ-II) in rheumatoid arthritis (RA). METHODS: Item response theory (IRT) analyses were performed on US (n = 18,747) and Dutch (n = 1,022) HAQ-II data to evaluate the equivalence of crosscultural item performance. The observed inconsistencies were modeled by assigning country-specific item parameters to biased items. The impact of crosscultural item bias on the comparability of the Dutch and US total scores was analyzed by evaluating the agreement between physical function levels estimated from an IRT model with country-specific item parameters for biased items and physical function levels estimated from the original model that did not account for cultural bias. RESULTS: Two items showed significant crosscultural bias. However, the agreement in physical function estimates between the respecified and original models was very high, with an intraclass correlation coefficient >0.99 and Bland-Altman limits of agreement ranging from -0.08 to -0.01 on a latent scale with a mean of 0 and an SD of 1. CONCLUSION: This study suggests that the Dutch and US HAQ-II produce total scores that can be interpreted interchangeably across countries in RA studies, despite some minor bias at the item level.

Construct validity of the interview time trade-off and computer time trade-off in patients with rheumatoid arthritis: a cross-sectional observational pilot study.

BACKGROUND: The Time Trade-Off (TTO) is a widely used instrument for valuing preference-based health-related quality of life (HRQoL). The TTO reveals preferences for own current health ('utilities') on a scale anchored between death (0) and perfect health (1). Limited information on the external validity of the TTO is available. Aim of this pilot study was to examine the construct validity of both an interview TTO and a computer-based TTO in patients with rheumatoid arthritis (RA). METHODS: Thirty patients visiting the outpatient rheumatology clinic participated. Construct validity was assessed by measuring convergent and discriminative validity. Convergent validity was assessed by calculating Spearman's correlations between the utilities obtained from the TTOs and pain, general health (rating scales), health-related quality of life (SF-36 and SF-6D) and functional status (HAQ-DI). Discriminative power of both TTO measures was determined by comparing median utilities between worse and better health outcomes. RESULTS: Correlations of both TTO measures with HRQoL, general health, pain and functional status were poor (absolute values ranging from .05 to .26). Both TTOs appeared to have no discriminative value among groups of RA patients who had a worse or better health status defined by six health outcome measures. About one-third of respondents were zero-traders on each of the TTO measures. After excluding zero-traders from analysis, the correlations improved considerably. CONCLUSIONS: Both the interview TTO and computer TTO showed poor construct validity in RA patients when using measures of HRQol, general health, pain and functional status as reference measures. Possibly, the validity of the TTO improves when using an anchor that is more realistic to RA patients than the anchor 'death'.

Long term follow-up of health-related quality of life in young adults born very preterm or with a very low birth weight.

BACKGROUND: The purpose was, first, to evaluate changes in health-related quality of life (HRQL) in a cohort of very low birth weight (VLBW; <1500 g.) or very preterm (< 32 weeks of gestation) children between ages 14 and 19, and second, to identify correlates of HRQL at age 19. METHODS: HRQL was assessed using the Health Utilities Index Mark 3 (HUI3). In order to explore correlates of HRQL, we performed a hierarchical regression analysis. RESULTS: Surviving VLBW children (n = 959) from a 1983 Dutch nation-wide cohort were eligible; 630 participated both at age 14 and 19; 54 at age 19 only. The mean HRQL score decreased from 0.87 to 0.86. The HRQL of 45% was stable, 25% were better and 30% were worse. A regression model showed internalizing problems were related most strongly to HRQL. CONCLUSIONS: In the transition from adolescence to young adulthood, HRQL in Dutch VLBW children was stable at the group level but varied at the individual level. HRQL was negatively associated with internalizing problems and also with physical handicaps. Long-term follow-up studies on the impact of VLBW on HRQL are all the more called for, given the growing number of vulnerable infants surviving the neonatal period.

Selection of items for a computer-adaptive test to measure fatigue in patients with rheumatoid arthritis: a Delphi approach.

PURPOSE: Computer-adaptive tests (CATs) can measure precisely at individual level with few items selected from an item bank. Our aim was to select fatigue items to develop a CAT for rheumatoid arthritis (RA) and include expert opinions that are important for content validity of measurement instruments. METHODS: Items were included from existing fatigue questionnaires and generated from interview material. In a Delphi procedure, rheumatologists, nurses, and patients evaluated the initial pool of 294 items. Items were selected for the CAT development if rated as adequate by at least 80% of the participants (when 50% or less agreed, they were excluded). Remaining items were adjusted based on participants' comments and re-evaluated in the next round. The procedure stopped when all items were selected or rejected. RESULTS: A total of 10 rheumatologists, 20 nurses, and 15 rheumatoid arthritis patients participated. After the first round, 96 of 294 items were directly selected. Nine items were directly excluded, and remaining items were adjusted. In the second round, 124 items were presented for re-evaluation. Ultimately, 245 items were selected. CONCLUSION: This study revealed a qualitatively evaluated item pool to be used for the item bank/CAT development. The Delphi procedure is a beneficial approach to select adequate items for measuring fatigue in RA.

Productivity loss due to absenteeism and presenteeism by different instruments in patients with RA and subjects without RA.

OBJECTIVES: To explore the impact of at-work productivity loss on the total productivity cost by different instruments in patients recently diagnosed with RA and controls without RA. METHODS: Cross-sectional data were collected from outpatients with RA between December 2007 and February 2008. The control group was formed by subjects without RA matched on age and gender. Absenteeism and presenteeism were estimated by the Quantity and Quality (QQ) Questionnaire, Work Productivity and Activity Impairment Questionnaire General Health V2.0 (WPAI-GH) and Health and Labor Questionnaire (HLQ) questionnaires. Differences between groups were tested by Mann-Whitney U-test. Costs were valued by the human capital approach. RESULTS: Data were available from 62 patients with a paid job and 61 controls. QQ- and WPAI-GH scores of presenteeism were moderately correlated (r = 0.61) while the HLQ presenteeism score correlated poorly with the other instruments (r = 0.34). The contribution of presenteeism on total productivity costs was estimated at ∼70% in the RA group. The mean costs per person per week due to presenteeism varied between €79 and €318 per week in the RA group, dependent on the instrument used. The costs due to presenteeism were about two to four times higher in the RA group compared with the control group. CONCLUSION: This study indicates that the impact of presenteeism on the total productivity costs in patients with RA is high. However, work productivity in individuals without RA was not optimal either, which implies a risk of overestimation of cost when a normal score is not taken into account. Finally, different presenteeism instruments lead to different results.

Application of the health assessment questionnaire disability index to various rheumatic diseases.

PURPOSE: To investigate whether the Stanford Health Assessment Questionnaire Disability Index (HAQ-DI) can serve as a generic instrument for measuring disability across different rheumatic diseases and to propose a scoring method based on item response theory (IRT) modeling to support this goal. METHODS: The HAQ-DI was administered to a cross-sectional sample of patients with confirmed rheumatoid arthritis (n = 619), osteoarthritis (n = 125), or gout (n = 102). The results were analyzed using the generalized partial credit model as an IRT model. RESULTS: It was found that 4 out of 8 item categories of the HAQ-DI displayed substantial differential item functioning (DIF) over the three diseases. Further, it was shown that this DIF could be modeled using an IRT model with disease-specific item parameters, which produces measures that are comparable for the three diseases. CONCLUSION: Although the HAQ-DI partially functioned differently in the three disease groups, the measurement regarding the disability level of the patients can be made comparable using IRT methods.

Rasch analysis of the Dutch Health Assessment Questionnaire disability index and the Health Assessment Questionnaire II in patients with rheumatoid arthritis.

OBJECTIVE: The Health Assessment Questionnaire (HAQ) disability index (DI) is the most common self-reported measure of physical disability in rheumatoid arthritis (RA). Recently, the HAQ-II was developed in the US as a short, valid, and reliable alternative using Rasch analysis. Our objective was to compare the scaling properties of the HAQ DI and HAQ-II in Dutch patients with RA. METHODS: We used data from 472 patients with confirmed RA. Internal construct validity of the HAQ versions was assessed using Rasch analysis. Additionally, external construct validity was assessed by examining correlates with other outcome measures. RESULTS: The HAQ DI had a large floor effect, with 9.5% of the patients indicating no disability compared with 4.3% for the HAQ-II. Both versions were unidimensional and adequately fit the Rasch model, containing only 1 nonfitting item. Additionally, 2 HAQ-II items demonstrated overfit and a high residual correlation, suggesting overlap or redundancy in item content. The HAQ-II demonstrated better item separation, indicating that it covered a wider range of physical function. Item difficulty estimates were reasonably well spread for the HAQ-II, whereas the HAQ DI items tended to cluster around similar difficulty levels. Both scales contained several items with differential item functioning by sex, age, or disease duration. Both scales demonstrated the expected pattern of correlations with other outcome measures. CONCLUSION: The results indicate that both the HAQ DI and HAQ-II are psychometrically robust measures of physical function. The Rasch-developed HAQ-II, however, has several favorable scaling properties, including a better scale length and a reduced floor effect.

Sexuality and people with intellectual disabilities: assessment of knowledge, attitudes, experiences, and needs.

The topic of sexuality and romantic relationships of people with mild to moderate intellectual disabilities was examined. We developed a questionnaire to investigate the 76 respondents' sexual knowledge, attitudes, experience, and needs. During the interviews, observational data were gathered to check the validity of the instrument. Results show that sexuality and romantic relationships are important aspects in the lives of many persons with intellectual disabilities. Male respondents generally reported more sexual needs than did females. Correlations were found between sexual knowledge and attitudes and between attitudes and experience or needs, suggesting that general behavioral models may be fruitfully used to further explore the topic of sexuality among people with intellectual disabilities.

Incorporating the patient perspective into outcome assessment in rheumatoid arthritis--progress at OMERACT 7.

The Patient Perspective Workshop at OMERACT 7 addressed the question of assessing the outcomes of intervention in rheumatoid arthritis (RA) from the perspective of those who experience the disease. A particular emphasis at this workshop was placed on fatigue, but other areas included well-being, real-time assessment, patient priorities, and needs in early and late disease. Through a series of overview presentations, discussion groups, and plenary sessions, workshop participants (who included 19 patients) clarified what is known and what are the outstanding issues for future research. The importance of further work on clarifying the validity of fatigue measurements in RA has been confirmed, and with at least one suitable instrument available there will be strong pressure to include fatigue in a redefined core set of outcome measures in RA. In the other 4 areas covered there are important issues that can be addressed by enquiry and experiment and that together provide a challenging research agenda. At the final plenary session the OMERACT conference endorsed, by a large majority, the proposal that fatigue may warrant consideration for inclusion in the OMERACT core set for RA.