The Report
The report was based on the study of the impact of depression screening on prenatal and post natal motherhood and effects of early interventions. A rigorous selection criterion was applied in collecting relevant data for analysis to answer key question (KQ) on the impact of early interventions.
The study was assessed against predetermined benchmarks to ensure good quality and reliable results. To attain high quality data, data validation and verification techniques were used in the research. The target population was fairly treated with adequate representation with sensitivity analysis appropriate performance ratings on the test sample.
Statistical Methods
The statistical procedures mentioned in the study included data collection techniques, sampling methods, the null and alternative hypotheses, probability distributions, the level and type of test done, and the rejection criteria on the significance of prenatal and post natal interventions (Crawshaw & Chambers, 2002, p. 509).
According to Gaynes, Gavin,Meltzer-Brody, Lohr, Swinson, Gartlehner, Brody and Miller (2005, p.4) a systematic research study was integrated in the evidence based study for accessing and retrieving data from electronic databases. Indexing was based on Author name, and article names were used to access and retrieve relevant data and information.
The research report indicated that mass screening of history subjects was done and an analysis of the effects of treatments was conducted. Of the total searches conducted, 837 unduplicated were identified, of which 9 were identified through handpicking, and 846 from discussions with TEAG. Other systematic reviews done included searches with perinatal and depressions, as the key words (Gaynes, Gavin, Meltzer-Brody, Lohr, Swinson, Gartlehner, Brody and Miller, 2005, p.6).
Though 50 searches fell short of meeting the inclusion and exclusion criteria, these results were identified to be influenced by the absence of established benchmarks against which they could be tested. This resulted in the elimination of 26 studies. In addition to that, various reasons identified for the exclusion criteria included lack of sensitivity and specificity, lack of depression outcome figures, and restrictions on certain sub groups (Gaynes, Gavin, Meltzer-Brody, Lohr, Swinson, Gartlehner, Brody and Miller, 2005, p.2).
A total of 59 studies were included in the study although less than that figure met the inclusion criteria (Gaynes et al., 2005, 2).
The Process and Significance Tests
A test sample on 15 patients with 11 successful early intervention cases were subjected to a hypothesis test. It was claimed in the study that early intervention was 90% successful on a 5 % significance test. The results were modelled by a binomial distribution independent of other patients, where X-B (15, p).
The Ho: p=0.9 (success of early intervention) and H: p<0.9 (success rate lower than 90%, according to the claim), where Ho is the null and H the alternative hypothesis. The claim could be rejected if, on a one tailed test for Ho the p (X≤x) < 5%, with 11 being the test value of x in the equations. Using cumulative binomial tables or calculating the probabilities directly, p (X≤11) =1-p (X≥12) = 1-0.9444 = 5.6%.
According to the statistical analysis of the representative population, the results were upheld.
The conclusion was appropriate since the p (X≤11) ≥ 5%. Implying that the lower tail of the distribution is to the left of x=11which is not in the critical region. Verifying and enforcing the claim early to interventions (Crawshaw & Chambers, 2002, p. 485).
The findings were statistically significant since a one tailed test was done on the alternative hypothesis with the p< 0.9 in the lower tail of the distribution.
The four basic approaches integrated in the study included, (1) the volume of studies, (2) sample sizes, (3) The degree of quality of each sample, and (4) Sample size representations.
References
Crawshaw, J & Chambers. (2002), J. Advanced Level Statistics with worked examples. 4th ed. Cheltenham: GL537TH, United Kingdom.
Gaynes, B. N., Gavin, N., Meltzer-Brody, S., Lohr, K. N., Swinson, T., Gartlehner, G., Brody, S., Miller, W. C. (2005). Perinatal Depression: Prevalence, Screening Accuracy, and Screening Outcomes.
Gaynes, B. N, Gavin, N, Meltzer-Brody, S., Lohr, K., N., Swinson, T, Gartlehner, G., Brody, S., Miller, W. C. (2005). Screening Accuracy.