Wound Healing Quantitative Research Critique

Vogt, Uhiyarik, & Schroeder (2007) conducted a study that compared Aquacel dressing vs. standard wound care for primary closed vascular surgical wounds. The results of the study found that there was no difference in length of stay in the hospital, complications, patient comfort, or healing time between the two wound care methods. The only difference was that the Aquacel dressing required fewer changes than conventional dressings, but that it increased the cost of care significantly. The following will analyze the methodology of the study and its conclusions in terms of clinical validity.

The design of the study was a randomized-controlled trial comparing standard dressing to Aquacel dressing for vascular surgical wounds. The study design directly reflected the intended purpose of the research, the research questions, the theoretical frame with work, previous literature, and the proposed hypothesis. All patients that participated in the study underwent elective vascular surgery.

Patients were randomized to either of the study groups. They would either be placed in the Aquacel group for wound care after surgery, or they would be placed in the standard wound care group after surgery. Randomization was allocated by a nurse by drawing a number corresponding to the group the patient would be assigned. Neither the researcher, the patient, nor the nurse knew to which group the patients would be assigned. The study involved 160 patients, with 80 in each of the control groups. The envelopes were not opened until the patients were in the surgical theater at the time of dressing application. This research design was appropriate as it represented a double blind assignment into groups. This eliminated the potential for researcher bias.

The randomization procedure used in this study was appropriate for the study, which compared to different groups of patients. Groups were of equal size which allowed direct comparison of the two methods being studied. The randomization procedure used for group assignment eliminated a potential...

There were no predetermined differences between the two groups of patients.
" Further design measures included exclusion of patients who were known to be sensitive to either of the wound dressing conditions that would be used. Patients that had dementia, who could not speak the native language of the area in which the surgery would be conducted, or who were pregnant were also excluded. Only patients were included that had an expected post operative hospital stay of at least four days. These measures helped to control for conditions that would serve as sources of bias in the sample population. The requirement for at least a four day hospital stay helped to ensure that the severity of the vascular surgery would be similar.

For patients that would receive multiple surgery sites, the same dressing was used on all of the surgery sites. This eliminated the possibility that difficulty healing wounds with one type of dressing would not interfere with wounds dressed with the other wound dressing method. It eliminated the potential that one wound dressing type would cause an immune system reaction that would affect would healing at all sites under different dressing conditions.

Although the preliminary design of the study appeared to be feasible and the randomization methods was not expected to interfere significantly with the surgical procedure, some conditions still existed that affected the equality of the two groups. Of the original 160 patients, 24 were excluded from the study at a later time. The three of the patients received the wrong type dressing according to their assigned number. Twelve patients were lost in the follow-up portion of the study. Three died, one underwent amputation, and one was transferred to intensive care. One was transferred to another hospital, and the observation reports of seven patients were not filled out properly. Nine patients had to receive a second surgery before follow-up. This left a total sample size of 136 patients. Although the final study group was…