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Biomedical subjects

J Alonso

Publications and source records attributed to J Alonso.

At least 127 records · Page 7Linked to original sources
PubMed1998

Lead content in edible wild mushrooms in northwest Spain as indicator of environmental contamination.

Lead content was determined in wild growing mushrooms collected from two different areas in the Province of Lugo (NW Spain). It has been analyzed by graphite furnace atomic absorption spectrometry in 95 samples of 13 species (7 mycorrhizals and 6 saprophites). In an assessment of lead concentrations, the following factors have been considered: species and ecology, morphological portion, and traffic pollution. The average lead concentration of the samples was 1 ppm dry weight (dw). Saprophite species presented higher levels than mycorrhizal ones (< 1 ppm), Coprinus comatus reaching the maximum mean concentration with 2.06 and 2.79 ppm of dw in the hymenophore and the rest of the fruit body. Morphological portion, statistically, did not show significant difference between the two portions; however, Macrolepiota procera always presented lead high levels in the hymenophore in all samples. The effect due to traffic pollution has been specially observed in Coprinus comatus, presenting the highest concentration with values of 6.51 and 10.43 ppm, respectively, in samples collected in the city center. This species, as other researchers have indicated, could be considered as an indicator by lead contamination. The contribution of mushrooms to the weekly intake of lead was calculated and the possible health risk for the consumer is pointed out. These data are of great importance in view of toxicology and partly environmental protection.

Basidiomycota↗
PubMed1998

Effectiveness of cataract surgery in Barcelona, Spain site results of an international study. Barcelona I-PORT investigators. International Patient Outcomes Research Team.

OBJECTIVES: To describe the impact of cataract surgery on visual function and health status in terms of clinical indicators as well as perceived health and functional capacity, and to identify patient characteristics and differences in clinical management that might affect outcomes. SUBJECTS AND METHODS: Observational longitudinal study of a cohort of 218 patients aged 50 or older undergoing first eye cataract surgery. Patients were evaluated pre- and postoperatively by clinical examinations (visual acuity [VA], ocular and medical comorbidity) and standardized telephone interviews. Main outcome measures included: the VF-14 Visual Function Index, the Cataract Symptom Score (CSS), the Sickness Impact Profile (SIP), and global measures of patients' trouble and satisfaction with vision. RESULTS: Significant improvement in all outcomes measures were observed at 4 months postoperatively (P < 0.001). However, the proportion of improved patients varied according to the outcome considered: VA (87%), CSS (72%), VF-14 (62%), and SIP (38%). Patient characteristics associated with higher a level of improvement were: worse preoperative visual function (VA, CSS, VF-14) (P < 0.001), less ocular comorbidity (P < 0.05), less postoperative complications (P < 0.05) and better preoperative general health status (SIP) (P < 0.01). The differences in clinical management were not associated with the outcomes (effectiveness) of surgery. CONCLUSIONS: A large proportion of patients benefit from cataract surgery, the greatest gain corresponding to visual function rather than to general health status. Since effectiveness of surgery is unrelated to operative procedures, less costly practices (i.e., day case surgery and loco-regional anesthesia) should be promoted.

Aged↗
PubMed1998

Translating health status questionnaires and evaluating their quality: the IQOLA Project approach. International Quality of Life Assessment.

This article describes the methods adopted by the International Quality of Life Assessment (IQOLA) project to translate the SF-36 Health Survey. Translation methods included the production of forward and backward translations, use of difficulty and quality ratings, pilot testing, and cross-cultural comparison of the translation work. Experience to date suggests that the SF-36 can be adapted for use in other countries with relatively minor changes to the content of the form, providing support for the use of these translations in multinational clinical trials and other studies. The most difficult items to translate were physical functioning items, which used examples of activities and distances that are not common outside of the United States; items that used colloquial expressions such as pep or blue; and the social functioning items. Quality ratings were uniformly high across countries. While the IQOLA approach to translation and validation was developed for use with the SF-36, it is applicable to other translation efforts.

Cross-Cultural Comparison↗
PubMed1998

Cross-cultural comparisons of the content of SF-36 translations across 10 countries: results from the IQOLA Project. International Quality of Life Assessment.

Increasingly, translated and culturally adapted health-related quality of life measures are being used in cross-cultural research. To assess comparability of results, researchers need to know the comparability of the content of the questionnaires used in different countries. Based on an item-by-item discussion among International Quality of Life Assessment (IQOLA) investigators of the content of the translated versions of the SF-36 in 10 countries, we discuss the difficulties that arose in translating the SF-36. We also review the solutions identified by IQOLA investigators to translate items and response choices so that they are appropriate within each country as well as comparable across countries. We relate problems and solutions to ratings of difficulty and conceptual equivalence for each item. The most difficult items to translate were physical functioning items that refer to activities not common outside the United States and items that use colloquial expressions in the source version. Identifying the origin of the source items, their meaning to American English-speaking respondents and American English synonyms, in response to country-specific translation issues, greatly helped the translation process. This comparison of the content of translated SF-36 items suggests that the translations are culturally appropriate and comparable in their content.

Cross-Cultural Comparison↗
PubMed1998

Testing the equivalence of translations of widely used response choice labels: results from the IQOLA Project. International Quality of Life Assessment.

The similarity in meaning assigned to response choice labels from the SF-36 Health Survey (SF-36) was evaluated across countries. Convenience samples of judges (range, 10 to 117; median = 48) from 13 countries rated translations of response choice labels, using a variation of the Thurstone method of equal appearing intervals. Judges marked a point on a 10-cm line-representing the magnitude of a response choice label (e.g., "good" relative to the anchors of "poor" and "excellent"). Ratings were evaluated to determine the ordinal consistency of response choice labels within a response scale; the degree to which differences between adjacent response choice labels were equal interval; and the amount of variance due to response choice label, country, judge, and interaction between response choice label and country. Results confirmed the hypothesized ordering of response choice labels; the percentage of ordinal pairs ranged from 88.7% to 100% (median = 98.2%) across countries and response scales. Examination of the average magnitudes of response choice labels supported the "quasi-interval" nature of the scales. Analysis of variance (ANOVA) results supported the generalizability of response choice magnitudes across countries; labels explained 64% to 77% of the variance in ratings, and country explained 1% to 3%. These results support the equivalence of SF-36 response choice labels across countries. Departures from the assumption of equal intervals, when observed, were similar across countries and were greatest for the two response scales that are recalibrated under standard SF-36 scoring. Results provide justification for scoring translations of individual items using standard SF-36 scoring; whether these items form the same scales in other countries as they do in the United States is evaluated with tests of scaling assumptions.

Analysis of Variance↗
PubMed1998

Testing the measurement properties of the Spanish version of the SF-36 Health Survey among male patients with chronic obstructive pulmonary disease. Quality of Life in COPD Study Group.

The aim of this article is to evaluate the measurement properties of the Spanish version of the SF-36 Health Survey (SF-36). In total, 321 male chronic obstructive pulmonary disease (COPD) patients attending hospital outpatient or primary health clinics were cross-sectionally administered the SF-36, the St. George's Respiratory Questionnaire (SGRQ), and a dyspnea scale. A clinical measure of respiratory function, the proportion of the predicted Forced Expiratory Volume in 1 second (%FEV1) was also obtained. Internal consistency, central tendency, and dispersion statistics of scores were calculated, as well as the percentage of respondents with the highest and lowest scores for each scale and correlations between health status and clinical measures. All patients completed the SF-36 questionnaire, and less than 1% of items were missing. The proportion of patients with the worst possible score (floor effect) ranged from 0.9-20.1% among the different scales. The proportion of patients achieving the best possible score (ceiling effect) ranged from 0-61%. Cronbach's alpha coefficients were above 0.75 except for one scale (Social Functioning, alpha = 0.55). SF-36 scores were moderate to highly correlated with SGRQ scores (coefficients ranged from -.41 to -.79). Correlations were moderate to high with dyspnea and lower but statistically significant with %FEV1. A clear gradient of SF-36 scores was found according to dyspnea levels and disease staging based on %FEV1 impairment, the gradient being more marked for the Physical Functioning, Role-Physical, and General Health scales. Data presented suggest that the Spanish version of the SF-36 is acceptable, valid, and reliable in COPD patients. Although more studies are needed, this version is adequate in international comparisons of health outcomes.

Adult↗
PubMed1998

Tests of data quality, scaling assumptions, and reliability of the SF-36 in eleven countries: results from the IQOLA Project. International Quality of Life Assessment.

Data from general population samples in 11 countries (n = 1483 to 9151) were used to assess data quality and test the assumptions underlying the construction and scoring of multi-item scales from the SF-36 Health Survey. Across all countries, the rate of item-level missing data generally was low, although slightly higher for items printed in the grid format. In each country, item means generally were clustered as hypothesized within scales. Correlations between items and hypothesized scales were greater than 0.40 with one exception, supporting item internal consistency. Items generally correlated significantly higher with their own scale than with competing scales, supporting item discriminant validity. Scales could be constructed for 93-100% of respondents. Internal consistency reliability of the eight SF-36 scales was above 0.70 for all scales, with two exceptions. Floor effects were low for all except the two role functioning scales; ceiling effects were high for both role functioning scales and also were noteworthy for the Physical Functioning, Bodily Pain, and Social Functioning scales in some countries. These results support the construction and scoring of the SF-36 translations in these 11 countries using the method of summated ratings.

Cross-Cultural Comparison↗
PubMed1998

Use of structural equation modeling to test the construct validity of the SF-36 Health Survey in ten countries: results from the IQOLA Project. International Quality of Life Assessment.

A crucial prerequisite to the use of the SF-36 Health Survey in multinational studies is the reproduction of the conceptual model underlying its scoring and interpretation. Structural equation modeling (SEM) was used to test these aspects of the construct validity of the SF-36 in ten IQOLA countries: Denmark, France, Germany, Italy, the Netherlands, Norway, Spain, Sweden, the United Kingdom, and the United States. Data came from general population surveys fielded to gather normative data. Measurement and structural models developed in the United States were cross-validated in random halves of the sample in each country. SEM analyses supported the eight first-order factor model of health that underlies the scoring of SF-36 scales and two second-order factors that are the basis for summary physical and mental health measures. A single third-order factor was also observed in support of the hypothesis that all responses to the SF-36 are generated by a single, underlying construct--health. In addition, a third second-order factors, interpreted as general well-being, was shown to improve the fit of the model. This model (including eight first-order factors, three second-order factors, and one third-order factor) was cross-validated using a holdout sample within the United States and in each of the nine other countries. These results confirm the hypothesized relationships between SF-36 items and scales and justify their scoring in each country using standard algorithms. Results also suggest that SF-36 scales and summary physical and mental health measures will have similar interpretations across countries. The practical implications of a third second-order SF-36 factor (general well-being) warrant further study.

Cross-Cultural Comparison↗
PubMed1998

Quality of life in severe chronic obstructive pulmonary disease: correlation with lung and muscle function.

UNLABELLED: Chronic obstructive pulmonary disease (COPD) patients suffer from significant impairment in quality of life (QL), but the variables related to this impairment are not well known. The aim of this study has been to identify physiological parameters related to QL in severe COPD patients undergoing long-term oxygen therapy. MATERIALS AND METHODS: We studied 47 COPD patients using long-term oxygen therapy (43 men/four women, 65.17 SD 8.21 years, 3.17 SD 2.61 years on oxygen). The Nottingham Health Profile (NHP) and activities of daily living (ADL) questionnaire were used to measure QL. Subjective assessment of dyspnoea was performed using a visual analogue scale. The physiological parameters determined were lung function (spirometry, arterial blood gases, lung volumes and carbon monoxide diffusing capacity), muscle function (maximum inspiratory and expiratory pressures, deltoid muscle and handgrip strength), and nutrition status (tricipital skin fold and mid-arm muscle circumference). RESULTS: High ADL (8.32 SD 6.97) and NHP scores (energy 63.3 SD 40.43, pain 35.11 SD 31.56, emotional reactions 43.03 SD 25.13, sleep 51.91 SD 32.75, social isolation 30.64 SD 26.98, physical mobility 49.73 SD 24.93) demonstrated clinically significant QL impairment in the severe COPD patients studied. Stepwise multiple regression analysis found a correlation between lung function and QL. Low FEV1% was associated with impairment in energy, physical mobility and social isolation NHP scores and ADL score (r = -0.3, P < 0.05). RV/TLC also correlated with ADL and social isolation scores (r = 0.3, P < 0.05). Lung function explained 39-45% of the variation in these QL dimensions. QL did not correlate with other lung function parameters, muscle function or nutrition status. CONCLUSION: COPD patients using long-term oxygen suffer from severe QL impairment affecting not only energy and mobility but also emotional reactions, social isolation and sleep. Lung function is related to energy, mobility and social isolation dimensions, but muscle function is unrelated to QL in these patients.

Aged↗
PubMed1998

Using the EuroQoI 5-D in the Catalan general population: feasibility and construct validity.

Spanish and Catalan versions of the EuroQoi 5-D (EQ-5D) were included in the Catalan Health Interview Survey (CHIS) and administered to a randomly selected cross-section of 12,245 individuals from the Catalan general population. This paper analyses the feasibility, convergent validity and construct validity of three parts of the EQ-5D (the descriptive system, the visual analogue scale (VAS) and the Spanish tariff) using the results obtained in the CHIS. The feasibility was assessed by the number of missing responses. The convergent validity was based on the correlations between the EQ-5D scores and the scores on the General Health Questionnaire (GHQ) and on an index of self-perceived overall health. The construct validity was assessed by analysing the degree to which lower scores on the EQ-5D correlated positively with increasing age, being female, being in a lower social class or having a lower level of education and with increasing levels of disability, co-morbidity, restricted activity, mental health problems and poor self-perceived health. A low number of missing responses on the descriptive system and the VAS (1.5%) indicated a high level of acceptance. A marked ceiling effect was found, with 67% of the sample reporting no problem in any EQ dimension. The convergent validity with the GHQ was generally low, though moderate on the mood dimension. Self-perceived overall health correlated moderately to strongly with the mean VAS and tariff values. The positive correlations between lower scores on all three elements of the EQ-5D and increasing age, increasing levels of disability, comorbidity, restricted activity, mental health problems and poor self-perceived health provide some evidence of the instrument's construct validity, as does the fact that women reported more problems than men. Multivariate analyses using the VAS and tariff values as dependent variables and all of the sociodemographic and health variables as independent variables reached R2 values of 0.45 and 0.81, respectively. The Spanish and Catalan versions of the EQ-5D have proved to be feasible and valid for use in health interview surveys.

Adolescent↗
PubMed1998

Emergency admission for cancer: a matter of survival?

The objective of this study was to compare the pre-hospital health care process, clinical characteristics at admission and survival of patients with a digestive tract cancer first admitted to hospital either electively or via the emergency department. The study involved cross-sectional analysis of information elicited through personal interview and prospective follow-up. The setting was a 450-bed public teaching hospital primarily serving a low-income area of Barcelona, Catalonia, Spain. Two hundred and forty-eight symptomatic patients were studied, who had cancer of the oesophagus (n = 31), stomach (n = 70), colon (n = 82) and rectum (n = 65). The main outcome measures were stage, type and intention of treatment and time elapsed from admission to surgery; the relative risk of death was calculated using Cox's regression. There were 161 (65%) patients admitted via the emergency department and 87 (35%) electively. The type of physician seen at the first pre-hospital visit had more often been a general practitioner in the emergency than in the elective group (89% vs 75%, P < 0.01). Emergency patients had seen a lower number of physicians from symptom onset until admission, but two-thirds had made repeated visits to a primary care physician. Emergency patients were less likely to have a localized tumour and a diagnosis of cancer at admission, and surgery as the initial treatment. Median survival was 30 months for elective patients and 8 months for emergency patients (P < 0.001), and the relative risk of death (RR) was 1.83 (95% confidence interval, CI, 1.32-2.54). After adjustment for strong prognostic factors, emergency patients continued to experience a significant excess risk (RR = 1.58; CI 1.10-2.27). In conclusion, in digestive tract cancers, admission to hospital via the emergency department is a clinically important marker of a poorer prognosis. Emergency departments can only partly counterbalance deficiencies in the effectiveness of and integration among the different levels of the health system.

Adult↗
PubMed1998

Influence of some factors in toxicity and accumulation of cadmium from edible wild macrofungi in nw Spain.

Cadmium content of 97 samples of some edible wild mushrooms, corresponding to 13 different species, was determined by graphite furnace atomic absorption spectrophotometry. Influence of some factors (species and ecology, morphological portion, and traffic pollution) and the importance of mushrooms as a dietary source of this heavy metal have been studied. Saprophite species showed higher levels than mycorrhizal ones (p < 0.001), with some exceptions such as Boletus and Amanita. The hymenophore was always the morphological portion which contained the highest cadmium levels (p < 0.001). Traffic pollution was not a significant factor for the cadmium accumulation in fungi. The samples of Agaricus macrosporus showed the highest mean levels (68.96 and 36.84 ppm dry matter (d. m.) for hymenophore and the rest of the fruit-body, respectively). The average cadmium content of the samples, with the exception of A. macrosporus, was 0.96 for hymenophore and 0.53 ppm d.m. for the rest of the fruit-body; and the range was between 0.18-4.32 and 0.10-1.91 ppm d.m. for hymenophore and the rest of the fruit-body. The concentration levels were compared to literature data and levels set by legislation, and the contribution of mushrooms to the weekly intake of cadmium per person was calculated. The possible health risk for the consumer is pointed out.

Basidiomycota↗
PubMed1998

Left-truncated data with age as time scale: an alternative for survival analysis in the elderly population.

BACKGROUND: The standard approach for survival analysis of the elderly population is to define the survival time as the elapsed time from entry into the study until death, and to adjust by age using stratification and regression procedures. However, the interest is in the study of the aging process and the risk factors related to it, not in the use of time-on-study as the time scale. Here, we present methods to use age as the time scale and compare inferences and interpretations with those obtained using the standard approach. METHODS: A total of 1,315 individuals aged 65 years or older from the city of Barcelona, Spain, were interviewed in 1986 (baseline). The vital status of the cohort was assessed in October 1994. To illustrate the usefulness of age as time scale (alternative approach) instead of time-on-study in the survival analysis of the elderly population, both methods were used to assess the relationship between baseline functional capacity and mortality. RESULTS: Using the alternative approach, we observed that 50% of the sample died at age 80.6 years; this information could not be estimated with the standard approach. Using age as a covariate in the standard analysis with time-on-study as the time scale and using age as the time scale in the alternative analysis, the association of functional capacity at baseline and mortality was of similar magnitude under both analyses. Nevertheless, using the alternative approach, relative risks were slightly lower, and the adjustment by age was tight and was not subject to the inherent assumptions in regression models of the functional relationship of independent variables with outcome. We illustrated the methods with fixed covariates (i.e., gender) and baseline values of time-dependent covariates (i.e., functional capacity), but we discussed the extension of our methods for the analysis of time-dependent covariates measured at several visits in a cohort study. Methods proposed here are easily implemented with widely available statistical software packages. CONCLUSIONS: Although the use of standard survival analysis generally produces correct estimates, the use of age as time scale is deemed more appropriate for survival analysis of the elderly: Inferences are easier to interpret and final models are simpler. We therefore recommend the use of age as time scale for survival analysis of the elderly population.

Aged↗
PubMed1998

Cross-cultural differences in the reporting of global functional capacity: an example in cataract patients.

OBJECTIVES: Patient-based health status measures have an important role to play in the assessment of health care outcomes. Among these measures, global assessments increasingly have been used, although the understanding of the performance of these indicators and the determinants of patients responses is underdeveloped. In this study, the performance of a single-item global indicator of visual function in cataract patients of four international settings was compared. METHODS: Visual acuity and ocular comorbidity was assessed by patients' ophthalmologist using Snellen-type charts in patients referred for a first cataract surgery in the United States, Manitoba (Canada), Denmark, and Barcelona (Spain). Patients also were interviewed by telephone and asked to report overall trouble with vision on a single-item indicator ("great deal," "moderate," "a little," "none") and to complete the Visual Functioning Index (VF-14), a scale of visual function ranging from 0 (worst function) to 100 (best level of function), along with other questions including the degree the patient was bothered by symptoms as measured by the Cataract Symptom Score (CSS). A total of 1,407 patients completed the clinical examination and the preoperative interview. RESULTS: Distribution of overall trouble with vision varied across the sites, with the proportion of patients reporting a great deal of trouble ranging from 21.7% to 37.9%. In all sites, patients reporting more trouble with vision tended to show a poorer age-adjusted and sex-adjusted visual acuity. The proportion of patients reporting great deal of trouble with vision was higher in the groups with worse visual acuity (P < 0.001). In multivariate analysis, after controlling for clinical and sociodemographic factors, the patients from Manitoba (OR = 0.32, 95% CI = 0.20, 0.51) and those from Barcelona (OR = 0.33, 95% CI = 0.20, 0.56) were less likely to report a great deal of trouble with their vision (P < 0.01) than the Danish and US patients. No such differences were found among the US patients from three sites. CONCLUSIONS: There is international variation in the self-reporting of global vision-related functional capacity that is not explained by clinical or sociodemographic factors, which may be because of cultural differences. International comparisons of patient-based health outcomes should not rely only on single-item indicators until there is convincing evidence of their cross-cultural equivalence.

Activities of Daily Living↗
PubMed1998

Variation in indications for cataract surgery in the United States, Denmark, Canada, and Spain: results from the International Cataract Surgery Outcomes Study.

BACKGROUND/AIMS: International comparisons of clinical practice may help in assessing the magnitude and possible causes of variation in cross national healthcare utilisation. With this aim, the indications for cataract surgery in the United States, Denmark, the province of Manitoba (Canada), and the city of Barcelona (Spain) were compared. METHODS: In a prospective multicentre study, patients scheduled for first eye cataract surgery and aged 50 years or older were enrolled consecutively. From the United States 766 patients were enrolled; from Denmark 291; from Manitoba 152; and from Barcelona 200. Indication for surgery was measured as preoperative visual status of patients enlisted for cataract surgery. Main variables were preoperative visual acuity in operative eye, the VF-14 score (an index of functional impairment in patients with cataract) and ocular comorbidity. RESULTS: Mean visual acuity were 0.23 (USA), 0.17 (Denmark), 0.15 (Manitoba), and 0.07 (Barcelona) (p < 0.001). When restricting the sample to eyes with normal retina and macula, no significant difference between United States and Denmark was observed (p > 0.05). Mean VF-14 scores were 76 (USA), 76 (Denmark), 71 (Manitoba), and 64 (Barcelona) (p < 0.001). CONCLUSION: Similar indications for cataract surgery were found in the United States and Denmark. Significantly more restricted indications were observed in Manitoba and Barcelona. Possible explanations for the results are discussed, including differences in sociodemographic characteristics, access to care, surgeons' willingness to operate, and patient demand.

Aged↗
PubMed1998

Respiratory symptoms, lung function and use of health services among unemployed young adults in Spain. Spanish Group of the European Community Respiratory Health Survey.

The association of respiratory symptoms, lung function and use of health services with employment status was examined in Spain, a country with a high rate of unemployment. A population sample comprising 179 unemployed and 1,868 employed subjects aged 20-44 yrs in 1993, was randomly selected from a base population of about 170,000 people in five urban and rural areas of Spain. Subjects completed a questionnaire on respiratory symptoms, sociodemographic and lifestyle factors, occupational exposure and use of health services, and performed a forced spirometry, a methacholine challenge test and blood tests. Unemployed subjects had a higher risk of simple chronic bronchitis (odds ratio=2.06, 95% confidence interval 1.30-3.24) and of bronchitis-type symptoms, than those who were employed. These risks were, in part, due to the higher prevalence of smoking, poorer housing and prior occupational exposures among unemployed than among employed people. Smaller differences were found between employed and unemployed subjects for asthma-type symptoms, atopia and lung function tests. Use of health services among subjects with respiratory symptoms was similar among employed and unemployed subjects, except that the latter consistently reported less frequent contact with specialized practitioners. Unemployed subjects had a higher risk of bronchitis-type symptoms than employed subjects. In Spain's national, free-access healthcare system, the differential use of specialized health services by employment status is likely to imply differences in the characteristics of the healthcare provided.

Adult↗