On May 1, 2009, Reuters Health reported that combined treatment with chemotherapy drugs topotecan and docetaxel is effective in treating women who had a return of uterine or ovarian cancer after having been treated with other drug combos. The study involved 15 women with recurrent ovarian cancer, 9 with recurrent uterine cancer, and 3 with cancer of the tissue lining the inside of the abdomen. The findings revealed that out of 24 women only six had complete response to treatment. This study sets to examine the statistical procedures mentioned in the report, describes the finding and conclusions and based on these analysis the study concludes whether they were appropriate or not.
Hypothesis Statement from the Cancer Research Report
The hypothesis statement is that combined treatment with the week chemotherapy drugs topotecan and docetaxel is effective for women who have had a return of their uterine or ovarian cancer and have already been treated with other drug combos.
Analysis of the Sampling Methods
The method used for selecting a sample from the population to study the effect of combined chemotherapy together with topotecan and docetaxel drug treatment was purposive non probability sampling. It is non probability because not all the members in the population were given an equal chance as opposed to random sampling. This method of sampling lacks accuracy because of the selection bias associated with it.
The sampling of 15 women with recurrent ovarian cancer, 9 with recurrent uterine cancer, and 3 with cancer of the tissue lining the inside of the abdomen was purposive in that it was to fulfill the specific purpose of investigating women with three different types of cancer. Other types of cancer like the lung cancer were left out, and also in this case only the women were targeted for this study. This purposive sampling method will therefore be limited in terms of inferences because it is confined and selective.
This technique is prone to sampling errors since a sample is chosen with the intention of obtaining specific results about effect of topotecan and docetaxel in treating ovarian, uterine and cancer of the tissue lining. Since the research was conducted by trained and competent personalities like Dr. Dr. Mark H. Einstein, from Albert Einstein College of Medicine, Bronx, New York, the sampling error due to faulty definitions and planning would not result.
Sampling Distribution
This clinical trial research draws inference from only one sample of 15 women with recurrent ovarian cancer, 9 with recurrent uterine cancer, and 3 with cancer of the tissue lining the inside of the abdomen and there has no sampling distribution. A sample distribution would only occur when more than one sample is undertaken and sample statistics computed. No sampling distribution means, standard deviation and variances are available for this study.
Discussion of the Findings and Conclusions
The research was comprehensive since it involved a total of 86 treatment cycles. And out of 27 participants selected fro inclusion in the sample results were established for 24 individuals which was a reasonable success rate. The cooperation from the participants ensured the success of the experiment. Of the 24 patients a mere 6 of the participants had a satisfactory response to treatment while another three had no worsening of their cancer. Six out of 24 individuals is a small number which may not merit making inference on the whole population because this represents a probability of only 0.25(6/24) or 25%. This implies that only 25 % of the patients with ovarian, uterine and cancer of the tissue lining could benefit from the treatment of topotecan and docetaxel while the rest 75% may not benefit from the program. The report by the Reuters Health that combined treatment with topotecan and docetaxel is effective in treating women with a return of uterine or ovarian cancer may not after all portent a breakthrough in cancer research because few women may stand to benefit.
Computation
Assuming a cancer population N of 480,000 individuals
The sample size n = 24
Sample proportion, p= 24/480,000= 0.00005
Therefore, q= 1-p= 0.99995
The Standard Error of p, SE (P) =pq/n=(0.00005X0.99995)/24= 2.0 X106
The 95% confidence interval for the population assuming a Z value of 2.58 is given by
=0.00005 + 2.58+ 2.0 X106 * (480,000-24)/(480,000-1)
=0.00005+ 0.048
The confidence interval for P is (0.04805, 0.04795) giving only about 23, 016 to 23, 064 individuals out of 480,000 population that could benefit from the treatment on a 95% confidence scale.
Appropriateness of the Statistical Procedures
Primary endpoint statistical analysis plan specify how the outcomes are measured. Binary measurements in the testing of combined chemotherapy together with topotecan and docetaxel drug treatment reveal that there was a partial response to the treatment with the odd ratio of complete treatment being at 0.25. The count which measures the frequent of the planned treatment in 86 cycles could not be established from the given data because no incidence density ratios are supplied. The time to event which typically measures the time it takes to see the outcome of treatment is censored because averaged hazard/risk ratios between groups are not available. Patients' preferences for intravenous, oral or combined treatment as a non-ordered ordinal scale were not reported in this cancer treatment.
Appropriate statistical tests such as correlation coefficients are not given there it will be difficult to test whether they are normally distributed. No mention is made on the t-tests, and F tests. If the said aforementioned statistical tests are not necessary the alternative statistical procedure such as category classification must be outlined. The original data on the patients was not categorized for instance if its good, acceptable or simply poor quality of life and besides mathematical transformations such as square roots and logarithms which are required to normalize the resulting variables are missing.
Conclusions
Based on the above problems and deficiencies in the data and results reported, it's a therefore follows that weekly dosing of topotecan and docetaxel is very unlikely to preserve their benefits while and decrease the side effects of cancer especially after prior treatments with other drugs. The standard clinical procedures were not fully followed and besides the outcome may not portent the best news for cancer patients for only a few stands to benefit from the breakthrough in treatment. Therefore the statistical procedures, findings and conclusions were inappropriate.
