Cross-cultural translation and validation of the IBD-control questionnaire in The Netherlands: a patient-reported outcome measure in inflammatory bowel disease.

BACKGROUND: There is a need for easy-to-use patient-reported outcome measures (PROMS) in inflammatory bowel disease (IBD) practice. The 'IBD-control' is a short IBD-specific questionnaire capturing disease control from the patient's perspective. The International Consortium for Health Outcomes Measurement (ICHOM) recommends the use of the IBD-control even though it has only been validated in the United Kingdom. We aimed to cross-culturally translate and validate the IBD-control in the Netherlands using IBDREAM, a prospective multicentre IBD registry. METHODS: Lack of ambiguity and acceptability were verified in a pilot patient group (n = 5) after forward-backward translation of the IBD-control. Prospective validation involved completion of the IBD-control, Short Form-36, short IBDQ and disease activity measurement by Physician Global Assessment (PGA) and Simple Clinical Colitis Activity Index or Harvey-Bradshaw Index. Test-retest (2-week repeat) was used for measuring reliability. RESULTS: Questionnaires were completed by 998 IBD patients (674 Crohn's disease, 324 ulcerative colitis). Internal consistency (Cronbach's alpha) was 0.82 for the sub-group of 8 questions (IBD-control-8-sub-score). Mean completion time was 105 s. Construct validity analyses demonstrated moderate-to-strong correlations of the IBD-control-8-subscore and the other instruments (0.49-0.81). Test-retest reliability for stable patients was high (intraclass correlation coefficient 0.95). The IBD-control-8-subscore showed good discriminant ability between the PGA categories (ANOVA, p<.001). Sensitivity to change analyses showed large effect sizes of 0.81-1.87 for the IBD-control-8 subscore. CONCLUSIONS: These results support the IBD-control as a rapid, reliable, valid and sensitive instrument for measuring disease control from an IBD patient's perspective in the Netherlands.

Physical activity and quality of life in long-term hospitalized patients with severe mental illness: a cross-sectional study.

BACKGROUND: Increasing physical activity in patients with severe mental illness is believed to have positive effects on physical health, psychiatric symptoms and as well quality of life. Till now, little is known about the relationship between physical activity and quality of life in long-term hospitalized patients with severe mental illness and knowledge of the determinants of behavioural change is lacking. The purpose of this study was to elucidate the relationship between objectively measured physical activity and quality of life, and explore modifiable psychological determinants of change in physical activity in long-term hospitalized patients with severe mental illness. METHODS: In 184 inpatients, physical activity was measured using an accelerometer (ActiGraph GTX+). Quality of life was assessed by EuroQol-5D and WHOQol-Bref. Attitude and perceived self-efficacy towards physical activity were collected using the Physical Activity Enjoyment Scale and the Multidimensional Self Efficacy Questionnaire, respectively. Patient and disease characteristics were derived retrospectively from electronic patient records. Associations and potential predictors were analysed using hierarchical regression. RESULTS: Physical activity was positively related with and a predictor of all quality of life outcomes except on the environmental domain, independent of patient and disease characteristics. However, non-linear relationships showed that most improvement in quality of life lies in the change from sedentary to light activity. Attitude and self-efficacy were not related to physical activity. CONCLUSIONS: Physical activity is positively associated with quality of life, especially for patients in the lower spectrum of physical activity. An association between attitude and self-efficacy and physical activity was absent. Therefore, results suggest the need of alternative, more integrated and (peer-)supported interventions to structurally improve physical activity in this inpatient population. Slight changes from sedentary behaviour to physical activity may be enough to improve quality of life.

Development of a web-based patient decision aid for initiating disease modifying anti-rheumatic drugs using user-centred design methods.

BACKGROUND: A main element of patient-centred care, Patient Decision Aids (PtDAs) facilitate shared decision-making (SDM). A recent update of the International Patient Decision Aids Standards (IPDAS) emphasised patient involvement during PtDA development, but omitted a methodology for doing so. This article reports on the value of user-centred design (UCD) methods for the development of a PtDA that aims to support inflammatory arthritis patients in their choice between disease modifying anti-rheumatic drugs (DMARDs). METHODS: The IPDAS development process model in combination with UCD methods were applied. The process was overseen by an eight-member multidisciplinary steering group. Patients and health professionals were iteratively consulted. Qualitative in-depth interviews combined with rapid prototyping were conducted with patients to assess their needs for specific functionality, content and design of the PtDA. Group meetings with health professionals were organized to assess patients' needs and to determine how the PtDA should be integrated into patient pathways. The current literature was reviewed to determine the clinical evidence to include in the PtDA. To evaluate usability among patients, they were observed using the PtDA while thinking aloud and then interviewed. RESULTS: The combination of patient interviews with rapid prototyping revealed that patients wanted to compare multiple DMARDs both for their clinical aspects and implications for daily life. Health professionals mainly wanted to refer patients to a reliable, easily adjustable source of information about DMARDs. A web-based PtDA was constructed consisting of four parts: 1) general information about SDM, inflammatory arthritis and DMARDs; 2) an application to compare particular DMARDs; 3) value clarification exercises; and 4) a printed summary of patients' notes, preferences, worries and questions that they could bring to discuss with their rheumatologist. CONCLUSIONS: The study demonstrated that UCD methods can be of great value for the development of PtDAs. The early, iterative involvement of patients and health professionals was helpful in developing a novel user-friendly PtDA that allowed patients to choose between DMARDs. The PtDA fits the values of all stakeholders and easily integrates with the patient pathway and daily workflow of health professionals. This collaborative designed PtDA may improve SDM and patient participation in arthritis care.

Validity and measurement precision of the PROMIS physical function item bank and a content validity-driven 20-item short form in rheumatoid arthritis compared with traditional measures.

OBJECTIVE: To evaluate the content validity and measurement properties of the Patient-Reported Outcome Measurement Information System (PROMIS) physical function item bank and a 20-item short form in patients with RA in comparison with the HAQ disability index (HAQ-DI) and 36-item Short Form Health Survey (SF-36) physical functioning scale (PF-10). METHODS: The content validity of the instruments was evaluated by linking their items to the International Classification of Functioning, Disability and Health (ICF) core set for RA. The measures were administered to 690 RA patients enrolled in the Dutch Rheumatoid Arthritis Monitoring registry. Measurement precision was evaluated using item response theory methods and construct validity was evaluated by correlating physical function scores with other clinical and patient-reported outcome measures. RESULTS: All 207 health concepts identified in the physical function measures referred to activities that are featured in the ICF. Twenty-three of 26 ICF RA core set domains are featured in the full PROMIS physical function item bank compared with 13 and 8 for the HAQ-DI and PF-10, respectively. As hypothesized, all three physical function instruments were highly intercorrelated (r 0.74-0.84), moderately correlated with disease activity measures (r 0.44-0.63) and weakly correlated with age (rs 0.07-0.14). Item response theory-based analysis revealed that a 20-item PROMIS physical function short form covered a wider range of physical function levels than the HAQ-DI or PF-10. CONCLUSION: The PROMIS physical function item bank demonstrated excellent measurement properties in RA. A content-driven 20-item short form may be a useful tool for assessing physical function in RA.

Working mechanism of a multidimensional computerized adaptive test for fatigue in rheumatoid arthritis.

BACKGROUND: This paper demonstrates the mechanism of a multidimensional computerized adaptive test (CAT) to measure fatigue in patients with rheumatoid arthritis (RA). A CAT can be used to precisely measure patient-reported outcomes at an individual level as items are consequentially selected based on the patient's previous answers. The item bank of the CAT Fatigue RA has been developed from the patients' perspective and consists of 196 items pertaining to three fatigue dimensions: severity, impact and variability of fatigue. METHODS: The CAT Fatigue RA was completed by fifteen patients. To test the CAT's working mechanism, we applied the flowchart-check-method. The adaptive item selection procedure for each patient was checked by the researchers. The estimated fatigue levels and the measurement precision per dimension were illustrated with the selected items, answers and flowcharts. RESULTS: The CAT Fatigue RA selected all items in a logical sequence and those items were selected which provided the most information about the patient's individual fatigue. Flowcharts further illustrated that the CAT reached a satisfactory measurement precision, with less than 20 items, on the dimensions severity and impact and to somewhat lesser extent also for the dimension variability. Patients' fatigue scores varied across the three dimensions; sometimes severity scored highest, other times impact or variability. The CAT's ability to display different fatigue experiences can improve communication in daily clinical practice, guide interventions, and facilitate research into possible predictors of fatigue. CONCLUSIONS: The results indicate that the CAT Fatigue RA measures precise and comprehensive. Once it is examined in more detail in a consecutive, elaborate validation study, the CAT will be available for implementation in daily clinical practice and for research purposes.

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.

Impact of patient-accessible electronic medical records in rheumatology: use, satisfaction and effects on empowerment among patients.

BACKGROUND: To measure the use, satisfaction and impact of a web portal which provides patients with rheumatoid arthritis home access to their electronic medical records (EMR). METHODS: A pretest-posttest study was conducted among 360 patients. Questionnaires assessed socio-demographics, health literacy, Internet use, disease characteristics, patient-provider relationship and empowerment before and after launching a hospital-based patient web portal. To measure the impact of the portal, patients' satisfaction with care, trust in their rheumatologist, self-efficacy in patient-provider communication, illness perceptions, and medication adherence were assessed. The post-test included questions on portal use, satisfaction, and self-perceived impact due to portal use. RESULTS: 54% of respondents with Internet access had viewed their EMR. Respondents were positive about the ease of use and usefulness of the portal and reported very few problems. Age (P = .03), amount of Internet use (P = .01) and self-perceived Internet skills (P = .03) significantly predicted portal use. Of the respondents who had logged in, 44% reported feeling more involved in their treatment and 37% felt they had more knowledge about their treatment. Significant differences over time were not found on the empowerment-related instruments. CONCLUSIONS: The current portal succeeded in offering patients access to their EMR in a usable and understandable way. While its true impact is difficult to grasp, a relevant portion of the patients felt more involved in their treatment due to the web portal. Offering patients home EMR access, therefore, appears to be a valuable addition to the care process.

Patient participation in decisions about disease modifying anti-rheumatic drugs: a cross-sectional survey.

BACKGROUND: Involvement of patients in decision-making about medication is currently being advocated. This study examined (the concordance between) inflammatory arthritis patients' preferred and perceived involvement in decision-making in general, and in four specific decisions about Disease-Modifying Anti-Rheumatic Drugs (DMARDs). Furthermore, this study examined how patients' involvement is related to satisfaction about decision-making and which factors are related to preferred roles, perceived roles and concordance. METHODS: Using a cross-sectional survey, 894 patients diagnosed with Rheumatoid Arthritis, Psoriatic Arthritis or Ankylosing Spondylitis were sent a questionnaire which focused on medical decisions in general and on four specific decisions: (a) starting with a traditional DMARD; (b) starting to inject methotrexate; (c) starting a biological DMARD; and (d) decreasing or stopping a DMARD. For each decision preferred and perceived involvement in decision-making was assessed using the Control Preference Scale. Concordance was calculated by subtracting the scores for perceived role from scores for the preferred role. Furthermore, satisfaction with the decision process and socio-demographic, health-related, patient-related and physician-related variables were assessed. RESULTS: The response rate was 58%. For all decisions, most patients (59%-63%) preferred Shared Decision-Making (SDM). SDM was perceived frequently (26%-55%) and patients' preferences were met in 54% of the respondents. Yet, in some specific decisions, 26% to 54% of patients would have liked more participation. Perceiving less participation then preferred was associated with less satisfaction with the decision-process, but perceiving more participation than preferred was not. Our results did not reveal any meaningful models to predict preferred or perceived participation in decision-making in general or with reference to specific decisions about DMARDs. CONCLUSIONS: Most arthritis patients prefer to be involved in decisions about their medication and SDM is perceived frequently. Yet, in some specific decisions patient participation can be further improved. Patients especially prefer more participation in decision-making regarding starting a first traditional DMARD, which occurs most commonly in newly diagnosed patients. Whereas perceiving too little participation was associated with decreased satisfaction, perceiving too much participation was not. Therefore, rheumatologists should urge patients to participate in every medical decision.

Performance of the Dutch SF-36 version 2 as a measure of health-related quality of life in patients with rheumatoid arthritis.

BACKGROUND: The aim of this study was to examine the measurement properties of the Dutch SF-36 version 2 (SF-36v2) health survey in patients with rheumatoid arthritis (RA). METHODS: Scaling assumptions, internal reliability, and internal construct validity were examined using available data from 1884 RA patients included in the Dutch Rheumatoid Arthritis Monitoring (DREAM) registry. External construct validity and responsiveness to change were examined using baseline and 6-month follow-up data from a subset of 387 early RA patients participating in the DREAM remission induction cohort. RESULTS: The individual items of the SF-36v2 adequately met scaling assumptions, although four items correlated too highly with items from different scales. Internal consistency was high for all eight scales and the physical and mental health components underlying the scales were replicated, supporting the use of the standard scoring algorithms. The SF-36v2 scales demonstrated minimal floor effects and ceiling effects were noteworthy only for the role-physical, social functioning, and role-emotional scales. Correlations with other core measures were as expected and the SF-36v2 showed excellent known-groups validity in distinguishing between patients with low or moderate-high disease activity. All scales related to physical health showed moderate to large responsiveness to change in patients that achieved low disease activity at six months. CONCLUSION: The SF-36v2 appears to be a psychometrically sound tool for the assessment of health-related quality of life of Dutch patients with RA.

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.

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.

Giving rheumatology patients online home access to their electronic medical record (EMR): advantages, drawbacks and preconditions according to care providers.

Technology enables patients home access to their electronic medical record (EMR), via a patient portal. This study aims to analyse (dis)advantages, preconditions and suitable content for this service, according to rheumatology health professionals. A two-phase policy Delphi study was conducted. First, interviews were performed with nurses/nurse practitioners (n = 9) and rheumatologists (n = 13). Subsequently, collected responses were quantified, using a questionnaire among the interviewees. The following advantages of patient home access to the EMR were reported: (1) enhancement of patient participation in treatment, (2) increased knowledge and self-management, (3) improved patient-provider interaction, (4) increased patient safety, and (5) better communication with others. Foreseen disadvantages of the service included: (1) problems with interpretation of data, (2) extra workload, (3) a change in consultation content, and (4) disturbing the patient-provider interaction. Also, the following preconditions emerged from the data: (1) optimal security, (2) no extra record, but a patient-accessible section, (3) no access to clinical notes, and (4) a lag time on the release of lab data. Most respondents reported that data on diagnosis, medication, treatment plan and consultations could be released to patients. On releasing more complex data, such as bodily examinations, lab results and radiological images the opinions differed considerably. Providing patients home access to their medical record might be a valuable next step into patient empowerment and in service towards the patient, provided that security is optimal and content and presentation of data are carefully considered.

A goal management intervention for polyarthritis patients: rationale and design of a randomized controlled trial.

BACKGROUND: A health promotion intervention was developed for inflammatory arthritis patients, based on goal management. Elevated levels of depression and anxiety symptoms, which indicate maladjustment, are found in such patients. Other indicators of adaptation to chronic disease are positive affect, purpose in life and social participation. The new intervention focuses on to improving adaptation by increasing psychological and social well-being and decreasing symptoms of affective disorders. Content includes how patients can cope with activities and life goals that are threatened or have become impossible to attain due to arthritis. The four goal management strategies used are: goal maintenance, goal adjustment, goal disengagement and reengagement. Ability to use various goal management strategies, coping versatility and self-efficacy are hypothesized to mediate the intervention's effect on primary and secondary outcomes. The primary outcome is depressive symptoms. Secondary outcomes are anxiety symptoms, positive affect, purpose in life, social participation, pain, fatigue and physical functioning. A cost-effectiveness analysis and stakeholders' analysis are planned. METHODS/DESIGN: The protocol-based psycho-educational program consists of six group-based meetings and homework assignments, led by a trained nurse. Participants are introduced to goal management strategies and learn to use these strategies to cope with threatened personal goals. Four general hospitals participate in a randomized controlled trial with one intervention group and a waiting list control condition. DISCUSSION: The purpose of this study is to evaluate the effectiveness of a goal management intervention. The study has a holistic focus as both the absence of psychological distress and presence of well-being are assessed. In the intervention, applicable goal management competencies are learned that assist people in their choice of behaviors to sustain and enhance their quality of life. TRIAL REGISTRATION: Nederlands Trial Register = NTR3606, registration date 11-09-2012.

Measuring actual eHealth literacy among patients with rheumatic diseases: a qualitative analysis of problems encountered using Health 1.0 and Health 2.0 applications.

BACKGROUND: The Internet offers diverse opportunities for disease management, through information websites (Health 1.0) and interactive applications such as peer support forums, online consults, and insight into electronic medical records (Health 2.0). However, various skills are required to benefit from Health 1.0 and Health 2.0 applications for one's own health, known as eHealth literacy. OBJECTIVE: To study the eHealth literacy of patients with rheumatic diseases and the types of problems they encounter when using the Internet in relation to their disease. METHODS: In two studies, patients were asked about their current disease-related Internet use and their eHealth literacy was observed during performance tests. In study 1, 15 patients (aged 39-74) performed 6 information-retrieval tasks on the Internet (Health 1.0). In study 2, 16 patients (aged 24-72) performed 3 Health 2.0 tasks on a hospital-based online Web portal and 2 Health 2.0 tasks on interactive websites. Participants were asked to think aloud while performing the assignments, and screen activities were recorded. Types and frequency of problems were identified by 2 independent researchers and coded into categories using inductive analysis. RESULTS: Almost all patients in our studies had searched the Internet for information about rheumatic diseases in the past. Fewer patients had used Health 2.0 applications, but many were nevertheless enthusiastic about the possibilities from Health 2.0 applications after finishing the assignments. However, nearly all participants experienced difficulties, and a substantial number of participants were not able to complete all of the assignments. Encountered problems could be divided into 6 sequential categories: (1) operating the computer and Internet browser, (2) navigating and orientating on the Web, (3) utilizing search strategies, (4) evaluating relevance and reliability, (5) adding content to the Web, and (6) protecting and respecting privacy. Most severe difficulties occurred in levels 3 and 4-in formulating a search query, evaluating the source of the information, and in scanning a website for relevant information. CONCLUSIONS: Many patients have insufficient skills to properly use Health 1.0 and Health 2.0. Formulating proper search strategies and evaluating the found information caused problems among the majority of patients. Concerning Health 2.0, use and awareness of these applications is low and patients should be guided in the use of them. Our findings may contribute to the awareness of patients' eHealth literacy problems among health professionals, and stress the importance of usability guidelines in Web design.

Worst-case future scenarios of patients with rheumatoid arthritis: a cross-sectional study.

OBJECTIVE: The time trade-off is a health-related quality of life instrument that measures valuations for health states (utilities) by asking patients to value their health state anchored on a scale between death (0) and perfect health (1). Dying earlier is not perceived as a realistic worst-case consequence of the disease by RA patients. Of the previous focus groups study on RA patients, five worst-case future scenarios emerged. The aim of this study was to examine which potential worst-case scenario was the most appropriate for RA patients to use in utility calculation. METHODS: In a cross-sectional study of 74 consecutive RA patients visiting the rheumatology outpatient clinic, participants were presented with descriptions of the five worst-case future scenarios. In pairwise comparisons, patients had to choose the scenario that would be the worst to experience. The worst-case future scenario was defined by the scenario that was chosen by a significantly greater proportion of participants than could be expected based on chance (20%). Therefore, analysis based on a single fraction ( ) was used and 95% CI was calculated. RESULTS: The scenario being dependent on others was chosen most often as the worst to experience [by 35% of participants (95% CI 24%, 46%)] and significantly more often than could be expected based on chance ( = 0.35, z = 6.45, P = 0.00). CONCLUSION: The scenario being dependent on others is likely to be the most appropriate worst-case future scenario for RA patients. Using an alternative anchor could improve the validity and responsiveness of the time trade-off in RA patients.

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.

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.

Modern psychometrics applied in rheumatology--a systematic review.

BACKGROUND: Although item response theory (IRT) appears to be increasingly used within health care research in general, a comprehensive overview of the frequency and characteristics of IRT analyses within the rheumatic field is lacking. An overview of the use and application of IRT in rheumatology to date may give insight into future research directions and highlight new possibilities for the improvement of outcome assessment in rheumatic conditions. Therefore, this study systematically reviewed the application of IRT to patient-reported and clinical outcome measures in rheumatology. METHODS: Literature searches in PubMed, Scopus and Web of Science resulted in 99 original English-language articles which used some form of IRT-based analysis of patient-reported or clinical outcome data in patients with a rheumatic condition. Both general study information and IRT-specific information were assessed. RESULTS: Most studies used Rasch modeling for developing or evaluating new or existing patient-reported outcomes in rheumatoid arthritis or osteoarthritis patients. Outcomes of principle interest were physical functioning and quality of life. Since the last decade, IRT has also been applied to clinical measures more frequently. IRT was mostly used for evaluating model fit, unidimensionality and differential item functioning, the distribution of items and persons along the underlying scale, and reliability. Less frequently used IRT applications were the evaluation of local independence, the threshold ordering of items, and the measurement precision along the scale. CONCLUSION: IRT applications have markedly increased within rheumatology over the past decades. To date, IRT has primarily been applied to patient-reported outcomes, however, applications to clinical measures are gaining interest. Useful IRT applications not yet widely used within rheumatology include the cross-calibration of instrument scores and the development of computerized adaptive tests which may reduce the measurement burden for both the patient and the clinician. Also, the measurement precision of outcome measures along the scale was only evaluated occasionally. Performed IRT analyses should be adequately explained, justified, and reported. A global consensus about uniform guidelines should be reached concerning the minimum number of assumptions which should be met and best ways of testing these assumptions, in order to stimulate the quality appraisal of performed IRT analyses.