Impact of outdoor air pollution on severity and mortality in COVID-19 pneumonia.

The relationship between exposure to air pollution and the severity of coronavirus disease 2019 (COVID-19) pneumonia and other outcomes is poorly understood. Beyond age and comorbidity, risk factors for adverse outcomes including death have been poorly studied. The main objective of our study was to examine the relationship between exposure to outdoor air pollution and the risk of death in patients with COVID-19 pneumonia using individual-level data. The secondary objective was to investigate the impact of air pollutants on gas exchange and systemic inflammation in this disease. This cohort study included 1548 patients hospitalised for COVID-19 pneumonia between February and May 2020 in one of four hospitals. Local agencies supplied daily data on environmental air pollutants (PM10, PM2.5, O3, NO2, NO and NOX) and meteorological conditions (temperature and humidity) in the year before hospital admission (from January 2019 to December 2019). Daily exposure to pollution and meteorological conditions by individual postcode of residence was estimated using geospatial Bayesian generalised additive models. The influence of air pollution on pneumonia severity was studied using generalised additive models which included: age, sex, Charlson comorbidity index, hospital, average income, air temperature and humidity, and exposure to each pollutant. Additionally, generalised additive models were generated for exploring the effect of air pollution on C-reactive protein (CRP) level and SpO2/FiO2 at admission. According to our results, both risk of COVID-19 death and CRP level increased significantly with median exposure to PM10, NO2, NO and NOX, while higher exposure to NO2, NO and NOX was associated with lower SpO2/FiO2 ratios. In conclusion, after controlling for socioeconomic, demographic and health-related variables, we found evidence of a significant positive relationship between air pollution and mortality in patients hospitalised for COVID-19 pneumonia. Additionally, inflammation (CRP) and gas exchange (SpO2/FiO2) in these patients were significantly related to exposure to air pollution.

Development of a decision tree to assess the severity and prognosis of stable COPD.

The aim of this study was to develop and validate a new method: a classification and regression tree (CART) based on easily accessible measures to predict mortality in patients with stable chronic obstructive pulmonary disease (COPD). This was a prospective study of two independent prospective cohorts: a derivation cohort with 611 recruited patients and a validation cohort with 348 patients, all followed for 5 yrs. CART analysis was used to predict 5-yr mortality risk using the following covariates from the derivation cohort: age, % predicted forced expiratory volume in 1 s (FEV(1)), dyspnoea, physical activity, general health and number of hospital admissions for COPD exacerbations in the previous 2 yrs. Age (≥ 75 or <75 yrs) provided the first branch of the COPD-CART. The highest mortality risk (0.74) was seen in patients >75 yrs of age with higher levels of dyspnoea and FEV(1) <50% pred. Patients with the lowest risk of 5-yr mortality (0.04) were <55 yrs of age with FEV(1) >35% pred and one or no recent hospitalisations for COPD exacerbations. A simple decision tree that uses variables commonly gathered by physicians can provide a quick assessment of the severity of the disease, as measured by the risk of 5-yr mortality.

Use of statistical techniques to synthesize explicit criteria developed by an expert panel.

OBJECTIVES: Methodology based on expert panels has been commonly used to evaluate the appropriateness of interventions. An important issue is the adequate synthesis of the generated information in an applicable way to clinical decision making. This paper shows how statistical procedures help synthesize the results of an expert panel. METHODS: Three statistical techniques were applied to an expert panel that developed explicit criteria to assess the appropriateness of total hip joint replacement: classification tree, regression tree and multiple correspondence analysis combined with automatic classification. RESULTS: Results provided by the three models were shown in graphical displays and were compared to the original panel results using crude and weighted probability of misclassification. Results were also applied to real interventions in order to know the implication of the misclassification on real patients. CONCLUSIONS: The statistical techniques help summarize data from panels of experts and provide useful decision models for clinical practice, especially when the number of indications is big. However, degree of misclassification and its implication should be taken into account.

Evaluation of explicit criteria for total hip joint replacement.

We tested an appropriateness of indications tool for total hip joint replacement in patients with osteoarthritis. Criteria were developed using a modified Delphi panel judgment process. Ratings were analyzed regarding level of agreement among panelists. Another panel rated the same indications; results were compared with the main panel. Test-retest of the main panel was performed. Regression models were used to assess the contribution of each algorithm variable. Appropriateness indication judgment was applied to 84 patients and compared to health-related quality-of-life improvement before and 3 months following intervention. Main panel ratings compared to those of a second panel resulted in a kappa statistic of 0.77. Test-retest kappa for the main panel was 0.81. Patients considered appropriate candidates for surgery, based on their composite indication scores, showed more improvement in health-related quality of life after 3 months than those considered inappropriately by composite indication scores. The previous parameters tested showed acceptable results for an evaluation tool. These results support the use of this indications algorithm as a screening tool for assessing the appropriateness of hip replacement surgery in osteoarthritis.

Development of explicit criteria for cholecystectomy.

OBJECTIVE: Consensus development techniques were used in the late 1980s to create explicit criteria for the appropriateness of cholecystectomy. New diagnostic and treatment techniques have been developed in the last decade, so an updated appropriateness of indications tool was developed for cholecystectomy in patients with non-malignant diseases. The validity and reliability of panel results using this tool were tested. METHODS: Criteria were developed using a modified Delphi panel judgement process. The level of agreement between the panelists (six gastroenterologists and six surgeons) was analysed and the ratings were compared with those of a second different panel using weighted kappa statistics. RESULTS: The results of the main panel were presented as a decision tree. Of the 210 scenarios evaluated by the main panel in the second round, 51% were found appropriate, 26% uncertain, and 23% inappropriate. Agreement was achieved in 54% of the scenarios and disagreement in 3%. Although the gastroenterologists tended to score fewer scenarios as appropriate, as a group they did not differ from the surgeons. Comparison of the ratings of the main panel with those of a second panel resulted in a weighted kappa statistic of 0.75. CONCLUSIONS: The parameters tested showed acceptable validity and reliability results for an evaluation tool. These results support the use of this algorithm as a screening tool for assessing the appropriateness of cholecystectomy.

Quality-of-life outcomes with laparoscopic vs open cholecystectomy.

BACKGROUND: Few studies have assessed the health outcomes of patients who underwent cholecystectomy. The goal of this study was to evaluate the health-related quality-of-life (HRQoL) improvement of patients undergoing laparoscopic versus open cholecystectomy. METHODS: A prospective observational study was performed of consecutive patients on waiting lists to undergo cholecystectomy for nonmalignant disease in six hospitals. Patients were asked to complete two questionnaires that measure (HRQoL)-the SF-36 and the Gastrointestinal Quality of Life Index (GIQLI)-before the intervention and 3 months later. RESULTS: Improvement after surgery, measured by the SF-36 and GIQLI, was similar for both surgical techniques. The SF-health transition item showed a perception of worse health, compared to 1 year previously, for those who underwent open surgery and complications were also higher. CONCLUSIONS: HRQoL improvement at 3 months was relevant and similar for both surgical techniques, although the health transition perception was worse for those who underwent open surgery.

[Use pf patient management categories (PMC) in the study of the variability of mean hospital stay for 3 surgical procedures]. / Uso del PMC en el estudio de la variabilidad de la estancia media hospitalaria en tres procesos quirúrgicos.

GOAL: To analyze variation in length of stay in acute hospitals by using a large administrative data base based on CMBD. SUBJECTS AND METHODS: Surgical patients admitted from 93 to 95 in the seven hospital with the largest volume of admissions from the Servicio Vasco de Salud--Osakidetza with a discharge diagnosis of inguinal hernia (IH), benign prostatic hyperplasia (BPH) and total hip joint replacement (THJR). We used data generated by a Patient Management Categories (PMC) data base. We present median length of stay result adjusted by age, sex, type of admission and Risk Intensity Score (RIS). We employed Analysis of Covariance (ANCOVA) for the multivariate analysis including the relevant interaction terms. RESULT: Adjusted median length of stay went from 2 to 6 days for IH patients, from 7 to 18 for BPH patients, from 5 to 18 for THJR patients; depending upon the different hospital and patient attributable considered confounders. By year, we saw a general decrease on length of stay. CONCLUSIONS: We found important differences by hospital though there is a decrease in length of stay in the last years. The administrative data bases, in spite of presenting validity problems, are a cheap and quick way of analyzing certain indicators to help in care management; given their limitations, cautious interpretation of the results is necessary.

[Patient satisfaction survey in emergency departments in acute care hospitals]. / Encuesta de satisfacción a pacientes de servicios de urgencias de hospitales agudos.

OBJECTIVE: To describe patient satisfaction with emergency care of different hospitals. METHODS: patients attended in emergency departments of nine acute hospitals. A patient satisfaction questionnaire was used which includes relevant areas for patients and emergency departments workers 1,940 patients were selected to be surveyed by phone, by previously trained interviewers. RESULTS: 1, 423 patients were interviewed. They reported that mean waiting time until were seeing by the physician ranged from 20 to 60 minutes and total time at the emergency room from 60 to 170 minutes. Interviewees negative ratings for both were of 38% and 36% respectively. Information given about the problem of the patient was negatively rated by 6 to 17%, and about the treatment to follow by 8 to 16% of them. 5% referred not getting information on the latest. Up to 30% of patients said not were clearly informed of the results of the test performed Interpersonal care was positively rated in 55% of cases in some hospitals. Global evaluation gave positive ratings of 58% and negatives of 14%. CONCLUSIONS: This survey detect significant differences among all the centers in the study. Waiting time area showed the greater differences among them. Also the worst qualifications, followed by information to patient. Patient satisfaction questionnaires may work as aid in detecting health care problems.

Cytotoxicity and cellular mechanisms involved in the toxicity of CdS quantum dots in hemocytes and gill cells of the mussel Mytilus galloprovincialis.

CdS quantum dots (QDs) show a great promise for treatment and diagnosis of cancer and for targeted drug delivery, due to their size-tunable fluorescence and ease of functionalization for tissue targeting. In spite of their advantages it is important to determine if CdS QDs can exert toxicity on biological systems. In the present work, cytotoxicity of CdS QDs (5 nm) at a wide range of concentrations (0.001-100 mg Cd/L) was screened using neutral red (NR) and thiazolyl blue tetrazolium bromide (MTT) assays in isolated hemocytes and gill cells of mussels (Mytilus galloprovincialis). The mechanisms of action of CdS QDs were assessed at sublethal concentrations (0.31-5 mg Cd/L) in the same cell types through a series of functional in vitro assays: production of reactive oxygen species (ROS), catalase (CAT) activity, DNA damage, lysosomal acid phosphatase (AcP) activity, multixenobiotic resistance (MXR) transport activity, Na-K-ATPase activity (only in gill cells) and phagocytic activity and damage to actin cytoskeleton (only in hemocytes). Exposures to CdS QDs lasted for 24h and were performed in parallel with exposures to bulk CdS and ionic Cd. Ionic Cd was the most toxic form to both cell types, followed by CdS QDs and bulk CdS. ROS production, DNA damage, AcP activity and MXR transport were significantly increased in both cell types exposed to the 3 forms of Cd. CAT activity increased in hemocytes exposed to the three forms of Cd while in gill cells only in those exposed to ionic Cd. No effects were found on hemocytes cytoskeleton integrity. Effects on phagocytosis were found in hemocytes exposed to bulk CdS and to CdS QDs at concentrations equal or higher than 1.25 mg Cd/L but not in those exposed to ionic Cd, indicating a particle-specific effect on phagocytosis. In conclusion, cell-mediated immunity and gill cell function represent significant targets for CdS QDs toxicity.

Microsatellites in immune-relevant regions and their associations with Maedi-Visna and ovine pulmonary adenocarcinoma viral diseases.

Maedi-Visna (MV) and ovine pulmonary adenocarcinoma (OPA) are two retroviral diseases occurring worldwide that affect adult sheep. Differences in incidence, which may be related to sheep-rearing and housing choices, as well as to genetics, and disease progression have been reported for both diseases. In this work four microsatellites located in immune-relevant regions, the major histocompatibility complex (MHC) region, interferon-γ and interleukin-12p35, were genotyped to determine their association with disease progression. The analysed sample included Latxa sheep with and without OPA and MV-characteristic lesions in their lungs. The microsatellites in the MHC were the most diverse, while the ones located in the cytokines were the less polymorphic. In the case of IFN-γ the results suggested the presence of null alleles. Significant results were detected for several microsatellite alleles in the association analysis carried out by logistic regression. All statistical analyses included a flock effect adjustment to avoid false positives due to genetic structuration. MHC Class I microsatellite alleles OMHC1*205 and OMHC1*193 were associated with disease progression for Maedi and OPA, respectively. Moreover, MHC Class II microsatellite allele DRB2*275 was associated with presence of lesions in Maedi. Furthermore, the MHC microsatellites were combined for a bioinformatic haplotype inference with the PHASE software. In total, 73 haplotypes were detected, 18 of them in more than 6 animals. After standard and weighted logistic regression analysis, two of them were significantly associated with susceptibility: OMHC1*205-DRB2*271 for Maedi and OMHC1*193-DRB2*271 for OPA, both with the Class I microsatellite alleles associated in the marker by marker study. Although more extensive analyses are needed to disentangle the relationship between host genetics and disease, as far as we know this is the first study demonstrating a significant association between sheep MHC Class I microsatellite alleles and susceptibility to Maedi-Visna and OPA viral diseases.

Responsiveness and clinically important differences for the WOMAC and SF-36 after total knee replacement.

OBJECTIVES: To study responsiveness and establish the minimal clinically important differences (MCIDs) and minimal detectable change (MDC) in patients undergoing total knee replacement (TKR) using the Short Form 36 (SF-36) and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). METHODS: Prospective observational study in three public hospitals of all consecutive patients on waiting lists to undergo TKR intervention with diagnosis of knee osteoarthritis (OA). Patients were asked to complete before the intervention and at 6 months and 2 years afterward the SF-36 and the WOMAC health-related quality of life questionnaires (HRQoL), and additional transition questions which measured the changes in their joint at 6 months. In both questionnaires the possible range of values is from 0 to 100 points. RESULTS: In WOMAC improvement at 6 months after a TKR was between 27 (stiffness) and 31 points (pain). The SF-36 showed improvements between the 28.3 points of role physical and 2.79 of general health. From 6 months to 2 years, WOMAC improvements were between 2 and 6 points. The MCID ranged from 14.52 (stiffness) to 22.87 (pain) on the WOMAC and in the physical domains of SF-36 from 11.56 (physical function) to 16.86 (bodily pain). On the WOMAC, the MDC ranged from 13.11 (function) to 29.12 (stiffness), and on SF-36 from 19.50 (physical function) to 41.23 (social functioning). CONCLUSIONS: The MCID for TKR is around 15 on WOMAC, while with the SF-36 of at least 10 points. These values should not be considered as absolute thresholds.

Influence of age and gender on quality-of-life outcomes after cholecystectomy.

Few studies have assessed the role of sociodemographic characteristics on outcomes after a cholecystectomy. Our goal was to evaluate the influence of age and gender on the health related quality of life (HRQoL) changes after cholecystectomy in this prospective observational study of consecutive patients undergoing cholecystectomy. Patients completed the SF-36 and the Gastrointestinal Quality of Life Index (GIQLI) before intervention and 3 months later. The influence of age, gender, and the pre-intervention health status on the HRQoL changes was studied by multivariate regression analysis. Older patients had poorer HRQoL and their post-intervention improvement was lower than younger patients. Compared with men, women had worse health status before the intervention measured with both HRQoL tools. In the unadjusted analysis women had greater improvements than men, measured by the GIQLI, but not with the SF-36. However, after controlling for other relevant variables, the SF-36 measured lower improvements in women more often than men, but the GIQLI showed similar results for both. For men and women, the lower the pre-intervention health status the higher the post-operative improvement. Women presented with worse health status before the intervention and less improvement post-operatively after adjustments. The pre-intervention health status has an important role explaining changes after the intervention. A gender-related difference exists between what a generic and a disease-specific HRQoL instrument captures when measuring HRQoL improvement after cholecystectomy.

Responsiveness and clinically important differences for the WOMAC and SF-36 after hip joint replacement.

OBJECTIVES: To study responsiveness and establish the minimal clinically important differences (MCID) and minimal detectable change (MDC) in patients undergoing total hip replacement (THR) using the Short Form 36 (SF-36) and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). METHODS: We conducted a prospective observational study in three public hospitals of all consecutive patients with a diagnosis of hip osteoarthritis (OA) on waiting lists to undergo THR. Patients completed the SF-36 and the WOMAC (subscales transformed to 0 to 100), which measured the health-related quality of life (HRQoL), before intervention and 6 months and 2 years later, and additional transitional questions, which measured the changes in the joint 6 months postoperatively. RESULTS: Improvements at 6 months after a THR were between 37 (stiffness) and 39 points (pain), depending on the WOMAC domain. The SF-36 domains also showed improvements: physical function (31.91), physical role (33.71), and bodily pain (29.77). From 6 months to 2 years, improvements ranged from 2 to 5 points, except for role physical (13.25). A ceiling effect was detected on some WOMAC domains as well as a floor effect on the SF-36. The MCID ranged from 25.91 (stiffness) to 29.26 (pain) on the WOMAC and from 10.78 (physical role) to 20.40 (physical function) on the SF-36. The MDC ranged from 21.38 (pain) to 27.98 (stiffness) on the WOMAC and from 18.99 (physical function) to 42.05 (social function) on the SF-36. CONCLUSIONS: These values indicate expected gains after THR. However, the MCID and MDC values must be viewed cautiously due to the uncertainty of these estimators and should not be considered as absolute thresholds.

Translation and psychometric testing of the Basque version of the SF-36 health survey.

INTRODUCTION: The primary goals of this study were to adapt the Short Form-36 (SF-36) questionnaire to the Basque language and to assess the translated questionnaire's psychometric properties. METHODS: Two pilot studies and a field study were conducted in 1999. The pathologies selected were hypertension, eating disorders, back pain, and HIV infection; blood donors were also included. The analyses conducted at item-level were: item internal consistency, item discriminant validity, equal item variance, and equal item-scale correlation. Internal consistency was measured at the scale level. Reproducibility, convergent validity and discriminant validity were also examined. RESULTS: 285 individuals took part in the study; sufficient data were obtained for 265 (93%). All items correlated higher than 0.4 with their hypothesized scales. Within each scale, item standard deviations were similar. Item-scale correlations were also similar. Cronbach's alpha coefficients varied from 0.76 to 0.92. In the test-retest reliability study, which included 54 additional individuals, all scales were above 0.50. Regarding the inter-scale correlation, the majority exceeded the 0.40 coefficient. In the correlation of similar scales of the SF-36 and the Nottingham Health Profile, intraclass correlation coefficient results ranged from 0.29 to 0.62. CONCLUSIONS: These results confirm that this new version of the SF-36 has been translated and adapted correctly for the Basque language and that it fulfils, at least partially, the psychometric properties required for this instrument. Further studies, however, are needed to completely validate the Basque version of the SF-36.

Changes in health related quality of life among patients treated for eating disorders.

OBJECTIVE: To prospectively investigate changes in the perception of health-related quality of life (HRQoL) among eating disorder patients after 2 years of treatment and follow-up and clinical predictors of change. METHOD: One hundred and thirty-one consecutive subjects were recruited from an eating disorder outpatient clinic. Subjects completed a generic HRQoL questionnaire, the Short Form-36 (SF-36), as well as the Eating Attitudes Test (EAT-40) to measure symptom severity and the Hospital Anxiety and Depression scale (HAD), at the first visit and after 24 months. RESULTS: Perception of HRQoL, measured by the SF-36, showed significant improvement in all but the role emotional domain after 2 years. The greatest improvements were observed in the physical function and social function domains, followed by mental health and vitality. Despite significant improvement in the summary mental health scale, scores after 2 years of treatment and follow-up were still below normative population values of women aged 18-34. Severity of eating disorder symptoms and presence of anxiety or depression at baseline significantly affected improvement in various SF-36 domains. CONCLUSIONS: Despite improvements in perception of HRQoL, eating disorder patients were more dysfunctional in all domains of the SF-36 even after 2 years of treatment and follow-up compared with women in the general population, and the severity of eating disorder symptoms was correlated with degree of dysfunction.

The health-related quality of life in eating disorders.

OBJECTIVE: This study investigated the perception of health-related quality of life (HRQoL) in ambulatory patients with eating disorders in relation to the severity of eating symptomatology and psychological comorbidity. METHODS: One hundred ninety-seven study patients were consecutively recruited at the Eating Disorders Outpatient Clinic. Short Form-36 items (SF-36), a generic HRQoL questionnaire, the Eating Attitudes Test (EAT-40), and the Hospital Anxiety and Depression Scale (HAD) were used to measure different aspects of HRQoL. The results of the SF-36 were compared with the norms of the Spanish general population for women 18-34 years of age. RESULTS: Patients with eating disorders were more dysfunctional in all areas of the SF-36 compared with women in the general population. There were no differences among the eating disorder diagnostic groups. Higher scores on the EAT-40 and the HAD were associated with a perception of greater impairment on all SF-36 subscales. CONCLUSION: The evaluation of HRQoL in these patients confirms the impact of these disorders on daily life in areas not directly related to eating disorders. The SF-36 is useful for discriminating among different levels of severity of eating disorders and other psychological comorbidities of these patients.

[Quality of life in patients with eating disorders]. / Calidad de vida de los pacientes afectados de trastornos de la alimentación.

OBJECTIVE: To evaluate the quality of life of ambulatory patients with eating disorders in relation to the severity of their symptomatology and in comparison with other psychiatric disorders and general population values. METHODS: Cross-sectional descriptive study of the quality of life of 180 patients recruited at an eating disorders unit. In order to study different aspects of their Health Related Quality of Life, the SF-36, the EAT and the HAD questionnaires were used. The results of the SF-36 were compared to population values of the same gender and age, and to other studies of psychiatric disorders where the SF-36 questionnaire was used. RESULTS: Patients with eating disorders presented worse quality of life than the general population of the same gender and age, and similar to patients with other psychiatric diagnoses, as schizophrenia, depression or panic disorder. No significant differences were found between patients with diagnoses of restrictive anorexia, purgative anorexia and bulimia. Mental health, rol emotional and vitality were the most affected areas of the SF-36. CONCLUSIONS: This study shows the severity of these disorders, which have a special incidence in young active women. This fact is becoming an important public health problem and raises the need of specialised assistance.

Predictors of improvement in health-related quality of life in patients undergoing cholecystectomy.

BACKGROUND: Few studies have assessed health-related quality of life (HRQoL) among patients undergoing cholecystectomy. This study aimed to determine clinical variables that predict changes in HRQoL following cholecystectomy. METHODS: This was a prospective study of consecutive patients undergoing elective cholecystectomy for gallstones in six hospitals. Patients were asked to complete two questionnaires-the Short Form 36 (SF-36) and the Gastrointestinal Quality of Life Index (GIQLI)-before and 3 months after cholecystectomy. Multivariate linear regression models were used to examine factors potentially contributing to changes in HRQoL. RESULTS: Patients with symptomatic cholelithiasis and low surgical risk experienced the highest HRQoL gains in several SF-36 and GIQLI domains, with significant improvements in physical function detected by both instruments, compared with asymptomatic individuals at high surgical risk. Patients with asymptomatic cholelithiasis or high surgical risk experienced least improvement. CONCLUSION: These data indicate that cholecystectomy is appropriate for patients with symptomatic cholelithiasis and low surgical risk. In terms of HRQoL, the risk to benefit ratio seems poor for patients with asymptomatic gallstones.

Evaluation of the psychometric characteristics of the Spanish version of the Hospital Anxiety and Depression Scale.

OBJECTIVE: To assess the psychometric properties of the Spanish version of the Hospital Anxiety and Depression Scale(HADS). METHOD: We administered HADS to 685 participants (256 controls and 429 patients with five different diagnoses). The reliability of the instrument was assessed by a test-retest study. Construct validity studies were carried out through item-subscale correlation and factor analysis for the whole group and by each of the five different diagnoses. Three instruments were used as external criteria to assess concurrent validity. RESULTS: HADS test-retest reliability presented correlation coefficients above 0.85. The internal consistency was high, with a Cronbach's alpha of 0.86 (anxiety) and 0.86 (depression). Factor analysis showed a clear two-factor structure for all groups. The results showed high concurrent validity with the Beck Depression Inventory and State-Trait Anxiety Inventory and with the mental domains of the Short-Form Health Survey. CONCLUSION: The Spanish version of the HADS demonstrated good reliability and validity when used in medical patients.

Evaluation by explicit criteria of the use of total hip joint replacement.

OBJECTIVE: To evaluate the appropriateness of the use of total hip replacement (THR) using explicit criteria developed by an expert panel. METHODS: Patients with a diagnosis of osteoarthritis who were undergoing THR in five public hospitals in Spain were included consecutively in the study during a 1-yr period. The appropriateness of the indication was judged by explicit criteria developed using a mutidisciplinary approach. Complications were measured 3 months after surgery. One year after discharge, pain, functional limitation and general health were measured. RESULTS: After evaluation of 583 patients, 82 (13.6%) were considered to have undergone inappropriate procedures, and for 279 (46.2%) patients indication for the procedure was considered uncertain. Differences were found in the rate of appropriateness among some centres. One year after discharge, the perception of general health was slightly better in those patients who had been judged to have undergone an appropriate procedure. CONCLUSIONS: The study identified a moderate percentage of inappropriately performed THR. When considered together with those cases that were judged to have uncertain indications, the results indicate that further studies should be done to identify patients who may have an inadequate benefit:risk ratio from this procedure.