Mean changes versus dichotomous definitions of improvement.

In recent years, when reporting the results of clinical trials for chronic disease, including rheumatologic conditions, use has been made of dichotomous definitions of improvement, but it is to be expected that continuous definitions would offer improved discrimination between treatment groups. Nevertheless, a well-constructed dichotomous outcome (usually a composite) has advantages of clinical sense and specificity and may, under a variety of realistic conditions, have power that closely approximates that of standard continuous outcome measures. This has been seen for established dichotomous outcome definitions for two rheumatologic conditions, rheumatoid arthritis (RA) and ankylosing spondylitis (AS). Simulation studies performed using multivariate normal generated data that approximates actual trial data for each of RA and AS patients demonstrate the relative power of several dichotomous and continuous outcomes in realistic situations for each of RA and AS. Although the continuous outcomes are typically more powerful than the dichotomous ones, there are some situations in which the power of a well-defined dichotomous outcome approaches or even exceeds that of a continuous outcome based on mean change.

High-dose melphalan and autologous stem-cell transplantation in patients with AL amyloidosis: an 8-year study.

BACKGROUND: AL amyloidosis is a fatal disease resulting from tissue deposition of amyloid fibrils derived from monoclonal immunoglobulin light chains. Treatment with oral chemotherapy is minimally effective. OBJECTIVE: To test survival and organ response in a large sample of patients treated with high-dose intravenous melphalan (100 to 200 mg/m2) and autologous blood stem-cell transplantation. DESIGN: 8-year longitudinal analysis of clinical effectiveness. SETTING: University-affiliated specialty referral clinic. PATIENTS: 701 consecutive new patients with AL amyloidosis. INTERVENTION: High-dose chemotherapy and autologous stem-cell transplantation for patients who met eligibility requirements based on organ involvement and clinical status. MEASUREMENTS: Survival analysis of all patients evaluated and a detailed analysis of treatment outcome in the subgroup that received high-dose melphalan and stem-cell transplantation. RESULTS: Among 701 patients with AL amyloidosis, 394 (56%) were eligible for high-dose melphalan and stem-cell transplantation; 82 did not proceed with treatment because of patient choice or disease progression. Median survival of the 312 patients who initiated treatment was 4.6 years. A complete hematologic response, defined as no evidence of an underlying plasma cell dyscrasia 1 year after treatment, was achieved in 40% of patients and was associated with prolonged survival. Statistically significant improvements occurred in end-organ disease and were greater in patients with a complete hematologic response. Mortality rate within 100 days of treatment with high-dose melphalan and stem-cell transplantation was 13%; patients with cardiomyopathy had the highest mortality rates. CONCLUSIONS: Treatment of selected patients with AL amyloidosis by using high-dose melphalan and stem-cell transplantation resulted in hematologic remission, improved 5-year survival, and reversal of amyloid-related disease in a substantial proportion.

Beta 2 microglobulin serum levels and prediction of survival in AL amyloidosis.

To study the relation between beta 2 microglobulin (beta 2M) and survival in AL amyloidosis, we measured the serum level of beta 2M in 80 patients with AL amyloidosis diagnosed within 1 year of evaluation, who had received no therapy. Patients had a median age of 61 years and 52% were male. Major clinical manifestations were renal disease in 25 patients (31%), cardiomyopathy in 23 patients (29%), and neuropathy or other organ involvement in 32 patients (41%). The beta 2M level, measured by an ELISA assay in serum samples collected at the time of evaluation, ranged from 1.69 to 10 mg/ml (mean = 4.57); in 56% of the patients beta 2M > 4 mg/ml. The patients with a beta 2M < or = 4 mg/ml had serum creatinine levels lower than those with beta 2M > 4 (1.43 vs 2.67 mg/dl; p = 0.02). Survival from study entry was analyzed overall by the level of beta 2M, adjusting for creatinine level and clinical stratum. We found the beta 2M level to be predictive of survival (median survival 16.1 months for beta 2M < or = 4 mg/ml vs 8.0 months for beta 2M > 4 mg/ml, p = 0.044). Thus a beta 2M level less than 4 mg/ml indicated a longer time of survival.

Diagnostic cost groups (DCGs) and concurrent utilization among patients with substance abuse disorders.

OBJECTIVE: To assess the performance of Diagnostic Cost Groups (DCGs) in explaining variation in concurrent utilization for a defined subgroup, patients with substance abuse (SA) disorders, within the Department of Veterans Affairs (VA). DATA SOURCES: A 60 percent random sample of veterans who used health care services during Fiscal Year (FY) 1997 was obtained from VA administrative databases. Patients with SA disorders (13.3 percent) were identified from primary and secondary ICD-9-CM diagnosis codes. STUDY DESIGN: Concurrent risk adjustment models were fitted and tested using the DCG/HCC model. Three outcome measures were defined: (1) "service days" (the sum of a patient's inpatient and outpatient visit days), (2) mental health/substance abuse (MH/SA) service days, and (3) ambulatory provider encounters. To improve model performance, we ran three DCG/HCC models with additional indicators for patients with SA disorders. DATA COLLECTION: To create a single file of veterans who used health care services in FY 1997, we merged records from all VA inpatient and outpatient files. PRINCIPAL FINDINGS: Adding indicators for patients with mild/moderate SA disorders did not appreciably improve the R-squares for any of the outcome measures. When indicators were added for patients with severe SA who were in the most costly category, the explanatory ability of the models was modestly improved for all three outcomes. CONCLUSIONS: Modifying the DCG/HCC model with additional markers for SA modestly improved homogeneity and model prediction. Because considerable variation still remained after modeling, we conclude that health care systems should evaluate "off-the-shelf" risk adjustment systems before applying them to their own populations.

Quality improvement implementation in the nursing home.

OBJECTIVE: To examine quality improvement (QI) implementation in nursing homes, its association with organizational culture, and its effects on pressure ulcer care. DATA SOURCES/STUDY SETTING: Primary data were collected from staff at 35 nursing homes maintained by the Department of Veterans Affairs (VA) on measures related to QI implementation and organizational culture. These data were combined with information obtained from abstractions of medical records and analyses of an existing database. STUDY DESIGN: A cross-sectional analysis of the association among the different measures was performed. DATA COLLECTION/EXTRACTION METHODS: Completed surveys containing information on QI implementation, organizational culture, employee satisfaction, and perceived adoption of guidelines were obtained from 1,065 nursing home staff. Adherence to best practices related to pressure ulcer prevention was abstracted from medical records. Risk-adjusted rates of pressure ulcer development were calculated from an administrative database. PRINCIPAL FINDINGS: Nursing homes differed significantly (p<.001) in their extent of QI implementation with scores on this 1 to 5 scale ranging from 2.98 to 4.08. Quality improvement implementation was greater in those nursing homes with an organizational culture that emphasizes innovation and teamwork. Employees of nursing homes with a greater degree of QI implementation were more satisfied with their jobs (a 1-point increase in QI score was associated with a 0.83 increase on the 5-point satisfaction scale, p<.001) and were more likely to report adoption of pressure ulcer clinical guidelines (a 1-point increase in QI score was associated with a 28 percent increase in number of staff reporting adoption, p<.001). No significant association was found, though, between QI implementation and either adherence to guideline recommendations as abstracted from records or the rate of pressure ulcer development. CONCLUSIONS: Quality improvement implementation is most likely to be successful in those VA nursing homes with an underlying culture that promotes innovation. While QI implementation may result in staff who are more satisfied with their jobs and who believe they are providing better care, associations with improved care are uncertain.

Barriers, facilitators, and access for wheelchair users: substantive and methodologic lessons from a pilot study of environmental effects.

We undertook a month-long intensive pilot study of a sample of adult wheelchair-users in Boston, Massachusetts and Durham, North Carolina, USA. The study had four objectives; to: (1) measure experiences of reaching and failing to reach specific destinations; (2) measure encounters with environmental facilitators and barriers, including both those overcome and not overcome; (3) determine the frequencies of destinations, facilitators, and barriers, and (4) test for consistency between daily reports and retrospective reports. Full participation entailed baseline and exit telephone interviews, and 28 daily telephone contacts. Participants reported reaching a wide range of destinations, most notably, banks, stores and shops, friends' and relatives' homes and health professionals' offices. There was a smaller range of destinations that they could not reach, despite trying; most notably, religious buildings, friends' and relatives' homes and work-places. They encountered an array of barriers, some of which they were able to overcome and others they could not overcome. Reported barriers included personal, interpersonal, and environmental barriers. The 25 subjects completing the study reported a wide range of human, environmental, and technologic support. In general, the consistency among daily, baseline, and exit interviews was high. This study has both substantive and methodologic implications. It suggests that efforts to facilitate social participation by wheelchair-users should focus not only on the built environment, but also on interventions in personal assistance and assistive technology, health promotion and fitness, and programs that improve civility. Methodologically, the data suggest that it is possible to make reliable measures of environmental encounters without the administrative and respondent burden associated with daily interviews.

Profiling resource use: do different outcomes affect assessments of provider efficiency?

OBJECTIVES: To examine whether 2 outcome measures result in different assessments of efficiency across 22 service networks within the Department of Veterans Affairs (VA). STUDY DESIGN: A retrospective analysis using VA inpatient and outpatient administrative databases. METHODS: A 60% random sample of veterans who used healthcare services during fiscal year 1997 was split into a 40% sample (n = 1,046,803) for development and a 20% sample (n = 524,461) for validation. Weighted concurrent case-mix models using adjusted clinical groups were developed to explain variation in 2 outcomes: "days of care"--the sum of a patient's inpatient and outpatient annual visit days, and "average accounting costs"--the sum of the average service costs multiplied by the units of service for each patient. Two profiling indicators were calculated for each outcome: an unadjusted efficiency index and an adjusted efficiency index. These indices were compared to examine network efficiency. RESULTS: Although about half the networks were identified as "efficient" before and after case-mix adjustment, assessments of individual network efficiency were affected by the adjustment. The 2 outcomes differed on which networks were efficient. For example, 4 networks that appeared as efficient based on days of care appeared as inefficient based on average costs. CONCLUSIONS: Assessments of provider efficiency across the 22 networks depended on the outcome measure used. Knowledge about the extent to which assessments of provider efficiency depend on the outcome measure used is an important step toward improved and more equitable comparisons across providers.

Proactive and reactive aggression in referred children and adolescents.

Investigating different types of aggression is important to facilitate a better understanding of excessive maladaptive aggression in referred youth. Using regression analysis, the authors investigated demographic, historical, diagnostic, and treatment correlates of proactive aggression and reactive aggression in a heterogeneous population (N = 323) of psychiatrically referred youths. Ratings of proactive and reactive aggression significantly correlated with more established measures of aggression. Results suggest the importance of hyperactive/impulsive behavior, disruptive behavior disorders, and self-reported hostility in youths with both reactive and proactive aggression. Substance use disorders, a family history of substance abuse, and family violence were specifically associated with proactive aggression. Younger age and a history of abuse were correlated with reactive aggression. Implications for clinical interventions and future research are discussed.

Analysis of an intervention to reduce parental anxiety prior to voiding cystourethrogram.

PURPOSE: The voiding cystourethrogram (VCUG) is a common imaging test in pediatric urology that can be associated with anxiety in the child and parent. We hypothesized that education by mailed brochure would decrease pre-procedure parental anxiety. METHODS: Families of children scheduled for VCUG were randomized into an experimental group that was mailed an educational brochure about the VCUG and a control group. Immediately prior to the procedure, parental anxiety was assessed with the self-administered State-Trait Anxiety Inventory (STAI). The parent repeated the STAI at home after the VCUG and answered brief questions about educational resources used to prepare for the VUCG. RESULTS: We enrolled 105 families (47 experimental, 58 control). Parental state anxiety was higher before the procedure than after the procedure (p < 0.001). Younger parents had greater pre-procedure state anxiety (p = 0.007). Contrary to our expectations, pre-procedure state anxiety did not differ between control and experimental groups. However, parents in the experimental group demonstrated less anxiety with some individual items in the questionnaire. CONCLUSION: An educational brochure mailed to families prior to VCUG did not decrease pre-procedure parental state anxiety. However, the educational brochure can ensure accurate dissemination of information to help families prepare for this potentially distressing procedure.

Durometry for the assessment of skin disease in systemic sclerosis.

OBJECTIVE: To examine the validity of a durometer to objectively measure skin hardness in systemic sclerosis (SSc), and to compare digital durometry with the modified Rodnan skin score (MRSS) and ultrasonography. METHODS: Patients with SSc and healthy controls underwent durometry measurements in 3 assessments: a Latin square experiment to establish durometry's intra- and interobserver reliability compared with skin scoring (5 SSc, 1 control); a longitudinal cohort to assess sensitivity to change in skin hardness (13 SSc, 5 controls); and an ultrasound cohort to evaluate correlation between durometry, ultrasound-measured skin thickness, and clinical skin scoring (30 SSc, 12 controls). RESULTS: Intraobserver reproducibility was higher for durometry than for clinical skin scoring (intraclass correlation coefficient [ICC] 0.97 versus 0.85), whereas interobserver reproducibility was similar (0.75 versus 0.73). Interobserver reproducibility of durometry was good for all body areas (ICC 0.61-0.85), but for skin scoring it was moderate in the legs (0.51) and poor in the abdomen (0.08), feet (0.09), and fingers (0.27). Durometry scores correlated with clinical skin scores (Latin square: r = 0.44, P = 0.03; longitudinal cohort: r = 0.81, P < 0.001) and ultrasound-measured skin thickness (hands: r = 0.58, forearms: r = 0.63, upper arms: r = 0.40; P < or = 0.001 for all). Uninvolved skin in patients with SSc was harder than skin from controls (mean +/- SD 23 +/- 7 durometer units [DU] versus 19 +/- 6 DU; P < 0.0001). Finally, there was a strong correlation between change in MRSS and change in durometry score (r = 0.77, P = 0.002). CONCLUSION: Durometer-measured skin hardness correlates well with MRSS and ultrasound-measured skin thickness, provides greater reliability than MRSS, and is sensitive to changes in skin hardness over time. Durometry should be considered for use in clinical therapeutic SSc trials.

Successful treatment of AL amyloidosis with high-dose melphalan and autologous stem cell transplantation in patients over age 65.

Recently, protocols using high-dose melphalan chemotherapy and autologous peripheral blood stem cell transplantation (HDM/SCT) have been developed for the treatment of patients with immunoglobulin light chain (AL) amyloidosis. Although peritransplantation mortality is greater than for other hematologic diseases, treatment leads to durable hematologic complete responses, improvements in organ function and quality of life, and extended survival in a substantial proportion of patients. To determine whether this treatment can be applied to older patients, we have analyzed HDM/SCT treatment outcomes for 65 patients (aged 65 years or older) with AL amyloidosis compared with outcomes for 280 younger patients. For patients over age 65 years who meet the same eligibility criteria as younger patients, toxicity, hematologic remission rate, and survival were not significantly different from those observed in younger patients, indicating that older patients should not be excluded a priori from consideration for HDM/SCT treatment.

Minimal disease activity for rheumatoid arthritis: a preliminary definition.

Agreement on response criteria in rheumatoid arthritis (RA) has allowed better standardization and interpretation of clinical trial reports. With recent advances in therapy, the proportion of patients achieving a satisfactory state of minimal disease activity (MDA) is becoming a more important measure with which to compare different treatment strategies. The threshold for MDA is between high disease activity and remission and, by definition, anyone in remission will also be in MDA. True remission is still rare in RA; in addition, the American College of Rheumatology definition is difficult to apply in the context of trials. Participants at OMERACT 6 in 2002 agreed on a conceptual definition of minimal disease activity (MDA): "that state of disease activity deemed a useful target of treatment by both the patient and the physician, given current treatment possibilities and limitations." To prepare for a preliminary operational definition of MDA for use in clinical trials, we asked rheumatologists to assess 60 patient profiles describing real RA patients seen in routine clinical practice. Based on their responses, several candidate definitions for MDA were designed and discussed at the OMERACT 7 in 2004. Feedback from participants and additional on-site analyses in a cross-sectional database allowed the formulation of 2 preliminary, equivalent definitions of MDA: one based on the Disease Activity Score 28 (DAS28) index, and one based on meeting cutpoints in 5 out the 7 WHO/ILAR core set measures. Researchers applying these definitions first need to choose whether to use the DAS28 or the core set definition, because although each selects a similar proportion in a population, these are not always the same patients. In both MDA definitions, an initial decision node places all patients in MDA who have a tender joint count of 0 and a swollen joint count of 0, and an erythrocyte sedimentation rate (ESR) no greater than 10 mm. If this condition is not met: * The DAS28 definition places patients in MDA when DAS28 < or = 2.85; * The core set definition places patients in MDA when they meet 5 of 7 criteria: (1) Pain (0-10) < or = 2; (2) Swollen joint count (0-28) < or = 1; (3) Tender joint count (0-28) < or = 1; (4) Health Assessment Questionnaire (HAQ, 0-3) < or = 0.5; (5) Physician global assessment of disease activity (0-10) < or = 1.5; (6) Patient global assessment of disease activity (0-10) < or = 2; (7) ESR < or = 20. This set of 2 definitions gained approval of 73% of the attendees. These (and other) definitions will now be subject to further validation in other databases.

Deriving an operational definition of low disease activity state in rheumatoid arthritis.

This article summarizes the process proposed to come to a definition of low disease activity in rheumatoid arthritis (RA). The purpose of this definition is to aid the interpretation of trial and longitudinal study results. A conceptual proposal is "a disease activity state that is deemed a useful treatment target by both physicians and patients." An operant definition can be derived by judgmental (opinion-based) or statistical (data-based) approaches, but the first seems more appropriate. Once a few candidate definitions have been selected, their usefulness and prognostic validity can be tested in longitudinal datasets.

Applying diagnostic cost groups to examine the disease burden of VA facilities: comparing the six "Evaluating VA Costs" study sites with other VA sites and Medicare.

OBJECTIVES: To compare the disease burden of Veterans Health Administration (VA) patients at six study sites with all other VA patients and the Medicare population. DESIGN: A 60% random sample of all VA veteran patients during federal fiscal year 1997 was obtained from administrative databases. A split-sample technique provided a 40% sample (n = 1,046,803) for development and a 20% sample (n = 524,461) for validation. We selected the six study sites from the 40% sample, yielding a total of 50,080 patients in those sites. METHODS: We used Diagnostic Cost Groups to classify patients into clinical groupings based on age, gender, and International Classification of Diseases, Ninth Revision, Clinical Modification diagnoses. The Diagnostic Cost Group model produces relative risk scores that describe patients' expected resource use normalized to the Medicare population. We compared the severity of the six sites with each other and with all other VA facilities and the severity of VA patients with that of Medicare beneficiaries. RESULTS: There were minor statistically significant differences between the study sites and all other VA facilities. Compared with the Medicare population, VA's population was younger and had lower expected resource use (relative risk scores were 1.0 and 0.76, respectively). CONCLUSIONS: Disease burden of the six study sites is representative of all other VA facilities. Although lower relative risk scores suggest that VA patients are healthier than Medicare beneficiaries, when age is taken into account, scores are more comparable. Interpreting the expected resource utilization of the VA population against other benchmarks should be performed carefully.

Comparison of rheumatoid arthritis clinical trial outcome measures: a simulation study.

OBJECTIVE: Isolated studies have suggested that continuous measures of response may be better than predefined, dichotomous definitions (e.g., the American College of Rheumatology 20% improvement criteria [ACR20]) for discriminating between rheumatoid arthritis (RA) treatments. Our goal was to determine the statistical power of predefined dichotomous outcome measures (termed "a priori"), compared with that of continuous measures derived from trial data in which there was no predefined response threshold (termed "data driven"), and to evaluate the sensitivity to change of these measures in the context of different treatments and early versus later-stage disease. In order to generalize beyond results from a single trial, we performed simulation studies. METHODS: We obtained summary data from trials comparing disease-modifying antirheumatic drugs (DMARDs) and from comparative coxib-placebo trials to test the power of 2 a priori outcomes, the ACR20 and improvement of the Disease Activity Score (DDAS), as well as 2 data-driven outcomes. We studied patients with early RA and those with later-stage RA (duration of <4 years and 4-9 years, respectively). We performed simulation studies, using the interrelationship of ACR core set measures in the trials to generate multiple trial data sets consistent with the original data. RESULTS: The data-driven outcomes had greater power than did the a priori measures. The DMARD comparison was more powerful in early disease than in later-stage disease (the sample sizes needed to achieve 80% power for the most powerful test were 64 for early disease versus 100 for later disease), but the coxib-versus-placebo comparison was less powerful in early disease than in later disease (the sample sizes needed to achieve 80% power were 200 and 100, respectively). When the effects of treatment on core set items were small and/or inconsistent, power was reduced, particularly for a less broadly based outcome (e.g., DDAS) compared with the ACR20. CONCLUSION: The simulation studies demonstrate that data-driven outcome definitions can provide better sensitivity to change than does the ACR20 or DDAS. Using such methods would improve power, but at the expense of trial standardization. The studies also show how patient population and treatment characteristics affect the power of specific outcome measures in RA clinical trials, and provide quantification of those effects.

Gender differences in reactive and proactive aggression.

The purpose of our investigation was to study gender differences in proactive and reactive aggression in a sample of 323 clinically referred children and adolescents (68 females and 255 males). Proactive aggression and reactive aggression were assessed using the Proactive/Reactive Aggression Scale. Demographic, historical, family, diagnostic, and treatment variables were entered into stepwise regression analyses to determine correlates of proactive and reactive aggression in males and females. Results reveal high rates of aggression in both males and females in the sample. Self reported drug use, expressed hostility, and experiences of maladaptive parenting were correlated with proactive aggression for both genders. Hyperactive/impulsive behaviors were correlated with male reactive aggression. An early age of traumatic stress and a low verbal IQ were correlated with female proactive aggression. Gender differences in correlates of proactive and reactive aggression may provide possible targets for research, prevention, and treatment efforts focused on reducing maladaptive aggression in clinically referred youth.

Relative costs and effectiveness of specialist and general internist ambulatory care for patients with 2 chronic musculoskeletal conditions.

OBJECTIVE: To evaluate costs and effectiveness of ambulatory care provided by specialists, nonspecialists (general internists), and both specialists and nonspecialists (co-care) to patients with knee osteoarthritis (OA) and/or chronic low back pain (LBP). METHODS: We studied Veterans Health Administration (VHA) outpatients from the Veterans Health Study with LBP and/or OA followed for at least 6 months between August 1993 and December 1995, who completed the Medical Outcomes Study Short Form 36-item (SF-36) functional status questionnaires at both baseline and followup. We obtained costs of VHA outpatient utilization and medications for these patients during the followup period. We compared costs and effectiveness of the ambulatory care provided by specialists, nonspecialists, and co-care. We also compared specialty care with nonspecialty care using an incremental cost effectiveness ratio (ICER) of annualized cost difference divided by annualized SF-36 based Physical Component Summary (PCS) improvement difference. ICER stability was assessed using bootstrap sampling. RESULTS: Among 398 patients, followed an average of 14 months, 155 received only nonspecialty care, 49 specialty-only care, and 192 co-care. After regression analysis, adjusted for age, disease characteristics, and baseline health status, PCS improvements per year were 1.66 (SD 8.22) for nonspecialty care, 3.48 (SD 7.91) for specialty care, and 0.65 (SD 8.08) for co-care; while costs of care per year were $1099 (SD $1681), $1376 (SD $1503), and $2517 (SD $1644), respectively (all data US dollars). A standardized ICER of $152 per PCS unit indicated specialty care to be cost effective compared with nonspecialty care. CONCLUSION: Specialist-only ambulatory care for OA or LBP was associated with improvement in functional status at slightly higher costs compared with nonspecialty care. Co-care, however, was substantially more costly and was associated with little improvement in functional status.

Improvement in quality of life of patients with AL amyloidosis treated with high-dose melphalan and autologous stem cell transplantation.

Treatment of AL amyloidosis patients with high-dose melphalan chemotherapy followed by autologous peripheral blood stem cell transplantation (HDM/SCT) can produce hematologic complete responses (CRs) and improvement in organ function. To determine whether these responses are accompanied by improvement in quality of life (QOL), we employed the Medical Outcomes Study (MOS) 36-item Short Form General Health Survey (SF-36) questionnaire for 544 patients evaluated between 1994 and 2002. At baseline, the scores were significantly lower on all 8 SF-36 scales compared with age-matched population norms: the composite physical component summary (PCS) for the AL patients was 34.5 versus the population norm of 46.8, and the mental component summary (MCS) was 45.0 versus the norm of 51.5. All SF-36 scores improved at 1 year, with the MCS reaching the population norm. The PCS, though improved, was still lower than normal but was greater in the subgroup of patients who achieved a hematologic CR; the PCS normalized at 2 years in these patients. Thus, treatment of AL amyloidosis patients with HDM/SCT produces measurable and sustained improvements in quality of life, particularly in those patients who achieve hematologic CR.

Outcome variables for osteoarthritis clinical trials: The OMERACT-OARSI set of responder criteria.

Improvement in analysis and reporting results of osteoarthritis (OA) clinical trials has been recently obtained because of harmonization and standardization of the selection of outcome variables (OMERACT 3 and OARSI). Moreover, OARSI has recently proposed the OARSI responder criteria. This composite index permits presentation of results of symptom modifying clinical trials in OA based on individual patient responses (responder yes/no). The 2 organizations (OMERACT and OARSI) established a task force aimed at evaluating: (1) the variability of observed placebo and active treatment effects using the OARSI responder criteria; and (2) the possibility of proposing a simplified set of criteria. The conclusions of the task force were presented and discussed during the OMERACT 6 conference, where a simplified set of responder criteria (OMERACT-OARSI set of criteria) was proposed.