Fahmi Khan

19 Questions 57 Answers 0 Followers

Questions related from Fahmi Khan

Can I do secondary post hoc analysis of previous study?

I have already conducted a study, however, after publication of this study, new question comes to my mind, can I do secondary analysis of this data to answer my new question?

11 November 2017 8,551 4 View

Is it important to get ethical approval for secondary data analysis?

I want to do secondary data analysis of my previous study; Is it important to get ethical approval for secondary data analysis?

11 November 2017 8,780 11 View

What is the appropriate sample size for this clinical trial?

I would like to conduct a clinical trial to do a head to head comparison between two drugs for safety and efficacy. How can I estimate the appropriate sample size?

10 October 2017 5,203 10 View

What are the minimum skill requirements needed for a person (student or physician) to become a researcher?

I have been asked this question by my colleagues (residents and physicians) several times. I would like to transmit this question to the experts like you to help them to get the appropriate answer.

03 March 2016 5,099 5 View

Relative risks and odds ratios: what’s the difference?

The measures of association, such as relative risk and odds ratio, reflect the strength of the relationship between an exposure and a disease. What’s the difference?

01 January 2014 2,920 9 View

What is the significance of publishing a manuscript in a journal with high impact factor?

Does the assessment of published article depend on the journal impact factor or on the content of the manuscript?

05 May 2013 3,011 11 View

How to use linear regression and correlation in quantitative method comparison studies?

Linear regression and correlation play an important part in the interpretation of quantitative method comparison studies. How to use linear regression and correlation in quantitative method...

05 May 2013 8,837 1 View

Which is the best statistical program for data analysis SPSS or SAS?

Researchers tend to have varying needs for statistical software to perform data analysis and as the market has much statistical software. It is difficult to choose the statistical program. Which...

05 May 2013 8,353 21 View

Can anybody tell me the differences between logistic regression test and linear regression test? When would we use each?

Regression test is an important test that has been used extensively in data analysis.Can anybody tell me the differences between logistic regression test and linear regression test? When would we...

05 May 2013 6,842 9 View

A patient with deep vein thrombosis under oral anticoagulants and INR of 2.9 wants to travel. How soon can he fly after a DVT?

05 May 2013 597 13 View

Can we start anticoagulants in a patient with pulmonary embolism who has massive hemoptysis? If the answer is no, how would we manage this patient?

...

05 May 2013 4,466 10 View

Is it necessary to have consent when conducting a retrospective study? If yes, from whom?

From ethical point of view, Is it necessary to have consent when conducting a retrospective study?

04 April 2013 6,712 39 View

Is it necessary to test the questionnaire before starting the study?

Is it necessary to test the questionnaire before starting the study? and how to do this?

03 March 2013 877 24 View

What is survival analysis? And what are the statistical methods to estimate survival time from data?

I am conducting a descriptive study on patients with liver transplantation. My mentor asks me to do survival analysis. What is survival analysis? And what are the statistical methods to estimate...

02 February 2013 6,292 15 View

While doing univariate and multivariate analysis, which is more reliable, Odds ratio or P value?

While I am doing a multivariate analysis, one variable showed odds ratio of 4.2 and P value off 0.01. How should I interpret this result?

02 February 2013 4,379 28 View

Is it possible to calculate the power of study retrospectively?

If we conducted a control study without determining the sample size and power of study, is it possible to calculate the power of study at the end (after data collection is completed)?

02 February 2013 5,499 40 View

Is it possible to test for significance between medians of two groups?

To perform a test of significance between means of two groups is well known. But if I use the medians is it possible to test for significance between medians of two groups?

02 February 2013 7,122 33 View

Which statistical test is appropriate to study the risk factor of a disease?

We are want to conduct a study to identify the risk factors for developing ventilator associated pneumonia in our intensive care unit. After identifying the control group, which test is suitable...

02 February 2013 2,695 15 View

Relative risks and odds ratios: What’s the difference?

The measures of association, such as relative risk and odds ratio, reflect the strength of the relationship between an exposure and a disease. What’s the difference?

11 November 2012 9,033 1 View