Critique of research methodology approaches and applications

Maxton, F.J.C., Justin, L. & Gillies, D. (2004). Estimating core temperature in infants and children after cardiac surgery: a comparison of six methods. Journal of Advanced Nursing 45(2): 214-22.

What is the research question? If it is not explicitly written, but is implicit in the article, suggest null and alternative hypotheses.

Which temperature-taking site yields the most accurate readings in babies and young children following cardiac surgery? Temperature is usually measured using the pulmonary artery as a "gold standard." However, the authors hypothesize that because the pulmonary artery cannot be used in the majority of the patients in the target population, other methods can and should be used. In addition to pulmonary artery temperature, the temperatures can be taken at the rectal, bladder, nasopharyngeal, axillary, and tympanic sites.

List the variables used in the study and identify each of them as either independent or dependent variables. Also describe the level or scale of measurement of each of them.

The independent variables are the sites at which temperature measures are taken on the infant or young child. These sites include the pulmonary artery, the rectum, bladder, nasopharyngeal area, axillary area, and tympanic sites. The dependent variables are the measure of variance between the core temperature taken at the pulmonary artery (the "gold standard") and the other sites. Thus, each site is being measured against the pulmonary artery temperature. The difference between the measurement of temperature at each site vs. The pulmonary artery temperature is the dependent variable.

3. List ALL the statistical analyses performed in the study, descriptive and inferential. What is the purpose of each of the analysis you listed?

Analyses of variance, used multiple times, are the primary statistical analysis used in the study. It is used because the primary method is to measure the variance between the target independent variable and the standard, which is the measure of temperature taken at the pulmonary artery. Differences between the two temperatures is computed, and compared with one another to determine which of the temperature sites is more accurate. Accuracy is considered to be whatever temperature is closer to that taken at the pulmonary site. An intraclass correlation was also used to determine which measures were closest to each other, too.

4.Describe the sample used in the study. Was the sample a good representation of the population that they were making inferences towards?

The sample was a convenience sample of 19 postoperative cardiac patients who are all infants or young children. The sample size is too small to yield results that are generalizable to the greater population. However, the results can suggest potential for future research using a larger sample size.

5. List the findings in the study and report on their level of significance.

The results of the study showed that there were no significant differences between the temperatures taken at the pulmonary artery and bladder. Results also showed that there were no significant differences between the temperatures taken at the pulmonary artery and the nasopharyngeal temperatures.

The closest relationship was between pulmonary artery temperature and temperature measured by a bladder catheter. The greatest difference, statistically speaking, was between pulmonary artery and axillary sites. There was also a great difference between pulmonary artery temperatures and rectal temperatures, and between pulmonary artery temperatures and tympanic measures. This would suggest that the axillary site temperature is the least effective or least accurate. There was also a statistically significant lag in time, between the pulmonary artery temperature and the rectal temperature: between 1 and 150 minutes. The total period of temperature taking time was six hours. The results show that bladder catheters yield the most accurate measures of temperature, if pulmonary artery temperature is considered to be the main benchmark. The nasopharyngeal probe yielded the next most accurate temperature results.