Biomedical Statistics
Question 7: The Level of Measurement
There are four different levels of measurement used by Lee et al. (2018). They include nominal, ordinal, interval, and ratio. The first measurement level is the nominal level, where the numbers are only useful in the classification of the data. In this regard, the examined selective symptoms such as dyspnea, depression, fatigue, and anxiety can only be represented in words, letters, and alphanumeric symbols. Hence, the four types of mental illness can be useful in depicting how they contribute to COPD.
The second one involves the ordinal level, where there is the depiction of the relationship between the levels of the variables used. Dyspnea was measured with forced expiratory volume in one second, which implies that the researcher could determine the rate at which the study participants were experiencing shortness of breath. It ranged from mild/temporary to a serious one. However, it is not easy to diagnose the problem because of various causes that may be causing it (Arvidsson, 2019). As a result, it was an ordinal level of measurement because it ranges from the highest level of the dyspnea problem, assigned as a serious one. The use of this form of measurement depicts the ordering of the measure since it ranges from a serious one to a temporary /mild one.
The third level of measurement is the interval, which is useful in the classification of the measure in order and specifies the severity of the problems in how they contribute to COPD. The variation in every interval level on the scale is equal from the lowest to the highest. For instance, this measurement level could involve the score of severity of anxiety problem of between ten and elven. The interval level of measurement in the Lee et al. (2018) case scenario was measured using the Likert scale, where it was easy to determine the anxiety, depression, and fatigue.
The last level of measurement is ration. Additional to equal intervals, there is a possibility of having zero also. The use of 0 is significant in causing differences with other forms of measurement even though it will still have similar properties to the interval measurement level (Holmes, Illowsky & Dean, 2015). There is a significant relationship between the division of points, form one to the next. In Lee et al. (2018), there was a six-minute walk test that was useful in determining the distance covered by the patients within six minutes. As such, it is easy to decide on the ratio of length walked from one patient to another, for instance, 1:2, 1:3, 1:4. Hence, the distance covered will help provide the rate at which one patient could walk compared to another patient.
Question 8: Inferential Statistical Technique
The inferential statistics used by Lee et al. (2018) include mean and the standard deviation. For instance, the authors were able to determine the number of males and females in the number of patients involved. There were three hundred and two patients who participated in the study. Amongst them, two hundred and eighty-two patients were provided with stopwatches. Besides, eighty percent were males with an average age of sixty-eight years (SD= ().
Similarly, 88% of the population were white non-Hispanic, and seventy-seven percent had completed college education. Also, sixty-one percent of the population had an income of twenty thousand dollars per year; fifty-eight percent were married or had partners. Standard deviation and mean were used in obtaining the original values before recording them into SEM. Thus, these techniques are useful for the generalizations of the results into other populations.
References
Arvidsson, R. (2019). On the use of ordinal scoring scales in social life cycle assessment. The International Journal of Life Cycle Assessment, 24(3), 604-606.
Holmes, A., Illowsky, B., & Dean, S. (2015). Levels of Measurement. Introductory Business Statistics.
Lee, J., Nguyen, H. Q., Jarrett, M. E., Mitchell, P. H., Pike, K. C., & Fan, V. S. (2018). Effect of symptoms on physical performance in COPD. Heart & Lung, 47(2), 149-156.