Estimating the Survival of Patients With Lung Cancer: What Is the Best Statistical Model?

Objectives: Investigating the survival of patients with cancer is vitally necessary for controlling the disease and for assessing treatment methods. This study aimed to compare various statistical models of survival and to determine the survival rate and its related factors among patients suffering from lung cancer. Methods: In this retrospective cohort, the cumulative survival rate, median survival time, and factors associated with the survival of lung cancer patients were estimated using Cox, Weibull, exponential, and Gompertz regression models. Kaplan-Meier tables and the log-rank test were also used to analyze the survival of patients in different subgroups. Results: Of 102 patients with lung cancer, 74.5% were male. During the follow-up period, 80.4% died. The incidence rate of death among patients was estimated as 3.9 (95% confidence [CI], 3.1 to 4.8) per 100 person-months. The 5-year survival rate for all patients, males, females, patients with non-small cell lung carcinoma (NSCLC), and patients with small cell lung carcinoma (SCLC) was 17%, 13%, 29%, 21%, and 0%, respectively. The median survival time for all patients, males, females, those with NSCLC, and those with SCLC was 12.7 months, 12.0 months, 16.0 months, 16.0 months, and 6.0 months, respectively. Multivariate analyses indicated that the hazard ratios (95% CIs) for male sex, age, and SCLC were 0.56 (0.33 to 0.93), 1.03 (1.01 to 1.05), and 2.91 (1.71 to 4.95), respectively. Conclusions: Our results showed that the exponential model was the most precise. This model identified age, sex, and type of cancer as factors that predicted survival in patients with lung cancer

Prospective Acid Reflux Study of Iran (PARSI): Methodology and study design

<p>Abstract</p> <p>Background</p> <p>Gastroesophageal reflux disease is a common and chronic disorder but long term, prospective studies of the fate of patients seeking medical advice are scarce. This is especially prominent when looking at non-erosive reflux disease (NERD) patients.</p> <p>Methods</p> <p>We designed a prospective cohort to assess the long term outcome of GERD patients referring to gastroenterologists. Consecutive consenting patients, 15 years of age and older, presenting with symptoms suggestive of GERD referring to our outpatient clinics undergo a 30 minute interview. Upper gastrointestinal endoscopy is performed for them with protocol biopsies and blood samples are drawn. Patients are then treated according to a set protocol and followed regularly either in person or by telephone for at least 10 years.</p> <p>Discussion</p> <p>Our data show that such a study is feasible and follow-ups, which are the main concern, can be done in a fairly reliable way to collect data. The results of this study will help to clarify the course of various subgroups of GERD patients after coming to medical attention and their response to treatment considering different variables. In addition, the basic symptoms and biological database will fuel further molecular epidemiologic studies.</p

Estimating the prevalence of positive tuberculin skin test reactions in general population and high-risk groups: A meta-analysis

Results of tuberculin skin test (TST) surveys among different populations have been reported in many studies as a method for detecting primary Mycobacterium tuberculosis infection. Combining these results provides reliable estimates of primary latent tuberculosis (TB) infection for health policymakers. This study aims to estimate the prevalence of latent TB infection in general and high-risk populations in Iran. National and international databanks were searched using specific keywords. After restricting the search strategy, duplicates exclusion, reviewing titles, abstracts and full texts, and quality assessment, eligible papers were selected. The heterogeneity between the results was assessed according to Cochrane and I-squared indices. The prevalence of positive TST reactions was estimated using fixed and random effect models. Totally, 33 papers were entered into the meta-analysis reporting the TST results in 12693 people aged over 18. The prevalence (95% confidence intervals) of positive TST reactions in all groups, general population, health staff, medical students, household close contacts, patients with TB, immunocompromised patients, HIV/AIDS patients, and those with risky behaviors was 26.2% (19.6–32.8), 25.4% (4.8–46.1), 38.9% (27.4–50.9), 13.4% (9.9–16.7), 35.9% (16.4–55.5), 13.7% (8.4–18.9), 29.4% (21.2–37.7), and 14.6% (3.9–25.3), respectively. Our study showed great varieties of positive TST results among different Iranian subpopulations. Furthermore, the prevalence of latent TB infection among health professionals and family members of TB patients was considerably different from that of the other subgroup. Since TB control programs such as active case finding are routinely conducted among household close contacts and HIV/AIDS cases, other high-risk groups including health-care workers and immunocompromised patients should be taken into consideration in these preventive programs

Prospective Acid Reflux Study of Iran (PARSI): Methodology and study design-1

<p><b>Copyright information:</b></p><p>Taken from "Prospective Acid Reflux Study of Iran (PARSI): Methodology and study design"</p><p>http://www.biomedcentral.com/1471-230X/7/42</p><p>BMC Gastroenterology 2007;7():42-42.</p><p>Published online 20 Nov 2007</p><p>PMCID:PMC2212633.</p><p></p> junction across the z-line, C: Cardia, D: Body, E: Antrum

Prospective Acid Reflux Study of Iran (PARSI): Methodology and study design-0

<p><b>Copyright information:</b></p><p>Taken from "Prospective Acid Reflux Study of Iran (PARSI): Methodology and study design"</p><p>http://www.biomedcentral.com/1471-230X/7/42</p><p>BMC Gastroenterology 2007;7():42-42.</p><p>Published online 20 Nov 2007</p><p>PMCID:PMC2212633.</p><p></p>Presenting just by minor symptoms

Prospective Acid Reflux Study of Iran (PARSI): Methodology and study design-2

<p><b>Copyright information:</b></p><p>Taken from "Prospective Acid Reflux Study of Iran (PARSI): Methodology and study design"</p><p>http://www.biomedcentral.com/1471-230X/7/42</p><p>BMC Gastroenterology 2007;7():42-42.</p><p>Published online 20 Nov 2007</p><p>PMCID:PMC2212633.</p><p></p> after one week. If patient is better with the previous prescription, patient should back to the previous dosage and continue till the next visit