The impact of participatory teaching methods on medical students' perception of their abilities and knowledge of epidemiology and statistics

Statistics and Epidemiology are crucial both in clinical decision-making and clinical research. Teaching these disciplines in a Bachelor’s Degree in Medicine is a significant challenge. In this paper, we aim to describe two participatory teaching methods used in a yearlong second-year course that includes both Epidemiology and Statistics, and to analyze how these two methodologies affect the students’ perception of the course and their abilities related to these subjects. Both methodologies consist in carrying out a specific practical activity. The first practical activity is carried out using a website and aims to help students understand concepts and interpret information; the second involves analyzing a database using a statistical package and, subsequently, producing a scientific report. In addition, we prepared a questionnaire to find out the students’ perception of these issues. The nine questionnaire items were assessed using a rating scale and adapted to characteristics of the course, which covers Epidemiology and Statistics in an integrated manner. Then we assessed the differences in perception before and after the activities were carried out. The results show that the students’ perception improved significantly in the following items: “importance of Statistics and Epidemiology in Medicine”; “usefulness in clinical practice”; “understanding concepts”; “ability to perform a statistical analysis”; and “ability to sort data”. The difference was not significant in the remaining four items. In conclusion, the students’ perception of their ability in Statistics and Epidemiology significantly improved after completing the practical activities, and their perception of importance and usefulness of these subjects also improved.

Nondisruptive p53 mutations are associated with shorter survival in patients with advanced non-small cell lung cancer

PURPOSE

TP53 mutations in early-stage non-small cell lung cancer (NSCLC) may be associated with worse survival but their prognostic role in advanced NSCLC is controversial. In addition, it remains unclear whether mutated patients represent a clinically homogeneous group.

EXPERIMENTAL DESIGN

We retrospectively examined TP53 mutations and outcome in a training cohort of 318 patients with stage IIIB-IV NSCLC: 125 epidermal growth factor receptor (EGFR) wild-type (wt) and 193 EGFR mutated (mut). An independent validation cohort of 64 EGFR-mut patients was subsequently analyzed. Mutations were classified as "disruptive" and "nondisruptive" according to their predicted degree of disturbance of the p53 protein structure and function.

RESULTS

In the training cohort, TP53 mutations were found in 43 of the 125 EGFR-wt patients (34.4%). Of these, 28 had nondisruptive TP53 mutations and a median overall survival (OS) of 8.5 months, compared with 15.6 months for the remaining 97 patients (P=0.003). In the EGFR-mut group, TP53 mutations were found in 50 of the 193 patients (25.9%). The OS for the 26 patients with TP53 nondisruptive mutations was 17.8 months versus 28.4 months for the remaining 167 patients (P=0.04). In the validation cohort, the 11 patients with nondisruptive TP53 mutations had a median OS of 18.1 months compared with 37.8 months for the 53 remaining patients (P=0.006). In multivariate analyses, nondisruptive TP53 mutations had an independent, significant association with a shorter OS.

CONCLUSIONS

Nondisruptive mutations in the TP53 gene are an independent prognostic factor of shorter survival in advanced NSCLC.

Single nucleotide polymorphisms in MDR1 gen correlates with outcome in advanced non-small-cell lung cancer patients treated with cisplatin plus vinorelbine

New therapeutic approaches are being developed based on the findings that several genetic abnormalities underlying NSCLC could influence chemosensitivity. In this study, we assessed whether the presence of polymorphisms in ERCC1, XPD, RRM1 and MDR1 genes can affect the efficacy and the tolerability of cisplatin and vinorelbine in NSCLC patients.

MATERIAL AND METHODS

Eligible patients had histological confirmed stage IV or IIIB (with malignant pleural effusion) non-small-cell lung cancer (NSCLC) previously untreated with chemotherapy; World Health Organization performance status (PS) 0-1. Patients received intravenous doses of vinorelbine 25 mg/m² on day 1 and 8 and cisplatin 75 mg/m² on day 1, every 21 days, for a maximum of eight cycles.

RESULTS

94 patients were included. Median age was 61 years; 84% were male; WHO performance status (PS) was 0 in 24%; and 88% of patients had stage IV disease. The median number of cycles was 6. Overall median survival was 10.92 months (95% CI 9.0-12.9). Overall median time to progression was 5.89 months (95% CI 5.2-6.6). Results of the multivariate analysis for time to progression showed that ECOG 0 (hazard ratio [HR] ECOG 1 vs. ECOG 0, 1.74; p=0.036), MDR13435CC (HR CT vs. CC, 2.01; p=0.017; HR TT vs. CC, 1.54; p=0.22), and decreasing age (HR of age, 0.97; p=0.016) were the most powerful prognostic factors significantly related to lower risk of progression. Whereas ECOG 0 was the only prognostic factor for survival (HR ECOG 1 vs. ECOG 0, 3.02; p=0.001). There was no significant association between any of the SNPs analysed and the occurrence of vinorelbine and cisplatin-related toxicity.

CONCLUSION

In our results, the most important prognostic factors associated with lower risk of progression were MDR1 3435 CC genotype, PS 0 and younger age.

[Retrospective, descriptive, observational study of treatment of multiple actinic keratoses with topical methyl aminolevulinate and red light: results in clinical practice and correlation with fluorescence imaging]

BACKGROUND

Actinic keratosis (AK) is one of the most common skin diseases seen in clinical practice. In the last 5 years, several studies assessing the efficacy of photodynamic therapy in the treatment of multiple AKs have been published.

OBJECTIVE

We aimed to assess the clinical outcomes of photodynamic therapy in patients with multiple AKs and the correlation of those outcomes with fluorescence imaging.

MATERIAL AND METHODS

In this retrospective, descriptive, observational study of 57 patients treated in our hospital with photodynamic therapy for multiple AKs, we recorded age, sex, and lesion site (face, scalp, and dorsum of the hands). All patients were treated in the same way: methyl aminolevulinic acid (Metvix) was applied for 3 hours and the skin then irradiated with red light at 630 nm, 37 J/cm(2), for 7.5 minutes (Aktilite). The response, remission duration, tolerance, number of sessions, and fluorescence images were recorded by site. The chi(2) test was used to assess between-site differences and the correlation between fluorescence imaging and clinical response.

RESULTS

The greatest improvements were obtained for facial lesions; these required fewer sessions and remission lasted longer than lesions at other sites. The treatment was best tolerated on the dorsum of the hands. The fluorescence area and the reduction in intensity on applying treatment were found to be strongly and significantly correlated with the extent of clinical response.

CONCLUSIONS

Overall, the outcomes of treatment of multiple AKs with photodynamic therapy are better for the face than for the scalp and dorsum of the hands. Fluorescence imaging may be an effective tool for predicting response to treatment.