Identify the independent variable and the primary dependent variable(s).

 

 

Each of the following questions can be addressed in a few sentences. If you find you are writing more than that, then you might be misreading the question or not being parsimonious. Please be succinct in responding. Each question is worth 1 point.

1.    The authors state that this study is a randomized controlled trial? What three properties characterize an RCT? Describe how each of these properties was included.

¢Â Â   According to Polit and Beck (2012), the three properties of a RCT include (1) manipulation or intervention, (2) the control group, and (3) randomization.

¢Â Â   In this study, the experimental intervention for experimental group was walking for 1 hour prior to reassessment. The alternative intervention for a control group was bed rest for 1 hour before reassessment. The randomization was done with a computer random number generator.

2.    Identify the independent variable and the primary dependent variable(s).

¢Â Â   The independent variable was different level of activity during a 1 hour labor check evaluation (bed rest or walking).

¢Â Â   The primary dependent variables were changes in cervical dilatation and the occurrence of delivery within 24 hours after reassessment.

3.    What are the secondary outcome variables?

¢Â Â   The secondary outcome variables were the participants™ comfort level during the 1-hour labor check evaluation, and the sensitivity and specificity of the 1-hour labor check to predict delivery within the next 24 hours.

4.    Did the researchers use a theoretical framework in this study? If yes, what theoretical framework was used? If no, identify an appropriate framework.

¢Â Â   There was no theoretical framework identified in this study. I think Martha Rogers™s Science of Unitary Human Beings is an appropriate framework for this study. The theory stated that the individual is a unified whole in constant interaction with the environment, and nursing helps individuals achieve maximum well-being within their potential (Polit & Beck, 2012).

5.    What type of sample was selected? How were subjects assigned to groups?

¢Â Â   The selected sample was convenience sample of 63 nulliparous full-term, low-risk women with an initial negative screen for active labor (cervical dilatation < 4cm; intact membranes).

¢Â Â   Subjects were randomly assigned to bed rest group (n=32) or walking group (n=31) by a computer random number generator, with group allocation sealed in opaque envelopes until just before the beginning of rest or walking period.

6.    How was patient comfort assessed? Was this an appropriate method to measure comfort? Support your response.

¢Â Â   A patient™s comfort level was assessed using a 100-mm vertical visual analog scale (VAS) with the lowest endpoint œ0 anchored by œExtremely Comfortable and the highest endpoint œ100 anchored by œExtremely Uncomfortable. After the patient making a mark on the vertical line, score of comfort level was calculated by measuring from the lowest end to the participant™s mark.

¢Â Â   I think this was an appropriate method to measure comfort level, since VAS scores have been found to be valid and reliable methods to measure subjective experiences, such as pain, fatigue, dyspnea, and comfort (Polit & Beck, 2012; Selby et al., 2012).

7.    Identify two possible threats to internal validity? How did the researchers control these threats?

¢Â Â   The first threat to internal validity was instrumentation or possible measurement error about the cervical dilatation. To control this threat, the researchers asked the same investigator to perform vaginal examinations for a patient before and after the rest or walking period.

¢Â Â   The second threat was maturation. The changes of cervical dilatation might occur as the passage of time rather than as a result of walking or bed rest. The researchers did not control this threat in the study.

8.    Identify how the primary dependent variable(s) was operationally defined?

¢Â Â   Changes in cervical dilatation were operationally defined by centimeter. A positive labor check evaluation means a change from baseline values in cervical dilatation of =1 cm after the 1-hour period; a negative labor check means no change or change <1 cm in cervical dilatation.

¢Â Â   The occurrence of delivery within 24 hours was operationally defined by yes or no. The delivery within 24 hours is likely with a positive labor check, whereas the delivery within 24 hours is not likely with a negative labor check.

9.    State one research hypothesis that was tested in this study (in a single sentence including variables, population of interest and a testable assertion).

¢Â Â   For nulliparous full-term, low“risk women with an initial negative exam for active labor between 37 to 42 weeks of gestation, the different activity levels during a 1-hour labor check evaluation would not affect the rate of cervical dilatation and the time to delivery.

10.    What was the sample size? How was the sample size determined?

¢Â Â   The sample size N= 63 was determined based on a power analysis with an effect size of 0.6 and a power of 0.80 and a=0.05.

11.    Was masking/blinding utilized? Why or why not?

¢Â Â   Masking or blinding was not utilized in this study, as the investigators who were performing vaginal examinations were aware of the participants™ group assignment. I think the reason of their inability to be blinded is that the study investigators are also members of the unit nursing staff, so they were aware of their patients™ activity in the unit.

12.    What baseline data was collected? Were there differences in baseline characteristics between the groups? If yes, what characteristics were different?

¢Â Â   The baseline date included age, labor characteristics (cervical dilatation, effacement, and station), and participants™ baseline comfort level on the VAS before intervention. There was no difference in baseline characteristics between the two groups.

13.    What is the level of measurement for the dependent variable(s)?

There are four dependent variables:

¢Â Â   Changes in cervical dilatation after intervention: Ratio measurement

¢Â Â   The occurrence of delivery within 24 hours after intervention: Nominal measurement

¢Â Â   The effect of activity level on comfort level: Ratio measurement

¢Â Â   The sensitivity and specificity of the 1-hour labor check evaluation to predict delivery within the next 24 hours: Ratio measurement

14.    What analysis (statistical test) was used to test for outcome differences following the intervention? Were the statistical tests appropriate?

¢Â Â   Student™s t-test was used to test for differences between the two groups for changes in cervical dilatation and comfort scores. The ?2 analysis was used to test for difference between the groups for occurrence of delivery within 24 hours.

¢Â Â   The statistical tests were appropriate. (1) The Student™s t-test, sometimes called independent t “test, is a two-sample location test applied to sets of interval or ratio data and the variances of the two groups are equal. This study meets these criteria. (2) The chi-square (?2) test is applied to sets of nominal data to test hypotheses about group differences in proportions. This study meets these criteria.

15.    State one implication for nursing research not offered by the researcher.

¢Â Â   As investigators in the study noticed improved nurse-patient relationships and had more confidence in the two results of vaginal examination when performed by the same nurse, one possible implication is that patients should be assigned to one nurse consistently throughout their stay on the unit to perform the labor check evaluation.