[Capacity for critical reading of clinical research among groups of medical residents]. / Capacidad de lectura crítica de investigación clínica en grupos de residentes médicos.

OBJECTIVE: To explore the association of length of clinical training and ability to read critically clinical research papers in groups of residents of internal medicine. MATERIAL AND METHODS: An instrument to evaluate critical reading was developed validated by four experts in clinical epidemiology. It contains four abstract from international medical journals. Each article was followed by 20 questions of false/true/ do not know options: 42 were interpretation items and 38 were judgement items. Each article had a semantic differential scale from 1 to 10 of global value of the paper. Seventy internal medicine residents participated: 20 in their first year of residency, 31 in the second year and 19 in the third year. RESULTS: There were no differences between overall scores according to year of training (global median score of 22.5 out of 80 as a maximum). Globally the interpretation items reached a median of 22 versus 9 in the in the judgement items (p < 0.01). A tendency to underestimate the validity of the articles by the residents was observed, i.e. their overall validity was significantly lower than that of the experts (p < 0.001). Finally, there was a correlation of 0.45 between the scores in this study and those obtained during their medical studies. CONCLUSION: These groups of residents were not influenced by length of their training during their internal medicine residency and their ability to judge clinical investigation papers.

[Ability of pediatric residents to read critically research papers]. / Lectura crítica de artículos de investigación por grupos de residentes pediatras.

OBJECTIVE: To explore ability to read clinical research papers by pediatric residents at different stages of their training. SETTING: Four hospitals of the Mexican Social Security System located in Mexico City. MATERIAL AND METHODS: An instrument to evaluate the ability to read critically pediatric research papers was developed and validated by four experts. It contained four abstracts generated from research articles and was integrated by 30 interpretation items, 30 judgment items and 30 alternative proposals items, to be answered by the true-false- don't know system. RESULTS: Sixty seven residents participated (21 first year, 20 second year and 26 third year level). There were no significant differences in interpretation, judgment and overall scores between groups. There was a significant degree of agreement in the ordinality of the residents for the scores in interpretation, judgment and proposals (Kendall W = 0.55, p < 0.001). CONCLUSIONS: We conclude that the residents were not influenced by the training received during their residence in regard to their ability for critical reading of clinical research papers.

[Usefulness of oral calcium test in renal lithiasis]. / Utilidad de la carga bucal con calcio en la litiasis renal.

We report the results of an oral tolerance test performed in 317 patients with kidney stones. In order to avoid PTH or AMPc measurements, and therefore to reduce costs and time to get the results, we measured the tubular maxima of phosphate per glomerular filtration rate (TmP04/GFR, the phosphate threshold). Urine collections from 7 to 9 h and from 9 to 13 h were obtained. The samples were analyzed for calcium, creatinine and phosphorus content. All patients ingested 1 g of calcium mixed in a meal at 9 o'clock. Venous blood samples were obtained for calcium, creatinine and phosphorus measurements, previous to the calcium ingestion. Urinary calcium to creatinine ratio, before and after the calcium-load, as well as TmP04/GFR were calculated. In 97 subjects (30.8%) there were no calcium metabolism abnormalities. Idiopathic hypercalciuria was present in 183 (57%) and primary hyperparathyroidism in 37 (11.7%). Idiopathic hypercalciuria was classified in four subgroups: absorptive hypercalciuria with normal serum phosphorus, absorptive hypercalciuria with low serum phosphorus (renal phosphate leak), renal hypercalciuria with normal phosphorus and renal hypercalciuria with low serum phosphorus.