This study seeks to show the direct relationship between the two, rather than the indirect relationship. Literature Review

This study took a somewhat unique approach to determining what affects a lower number of nurses on staff has on a deviation for expected length of stay (LOS) in a hospital.

Other research has focused primarily on the length of stay, not on the expected length of stay. The difference between the two approaches includes the fact that previous studies have shown that there is a difference in the quality of care and the length of stay in the hospital, but this is one of the first studies to take into account the expected length of stay and the deviation based upon the quality of care and the number of nurses on duty. Other studies and the literature that is derived from those studies presents findings that include; "increased nurse staffing levels have been linked to a reduction in several patient complications, including mortality rates" (Aiken, Clarke, Cheung, Sloane & Silber, 2003; Needleman, Buerhaus, Mattke, Stewart & Slevensky, 2002; Sasichay-Akkadechanunt, Scalzi & Jawad, 2003; Tourengau, Giovannetti, Tu & Wood, 2002). The literature shows the positive aspects of higher nursing numbers on staff as shown by the lower mortality rates, as well as other positive affects including length of stay. However, this study was conducted in order to determine the deviation from the expected length of stay, not on the length of stay itself. This particular aspect had not been considered in other previous literature.

Study Design

The study's design was quantitative in nature and appropriate because the measurements were statistical and verifiable by categorization. A specific number of nurses would always be on staff, there would certainly be enough patients admitted and discharged throughout the course of the study and the expected length of stay would be based on specific circumstances. As with any study, there were a number of threats to the validity of the findings. Those threats...

The internal threats were that the nurses who participated in the survey were biased. This is almost certainly true, due to the fact that nurses know that their jobs are in peril, and would answer the questionnaire accordingly. Additionally, the study would have to take into account that the expected length of stay is not a concrete measure, but it is one that is subjective based on the doctor's opinion, the nature of the illness, how severe the illness is perceived, and the exact diagnosis.
External validity could be compromised by the fact that these hospitals were both Midwestern facilities. It is conceivable to think that perhaps individuals in Midwestern cities react differently to hospitalizations than people from other parts of the country. Another compromise could be that the medical facility was a university facility and presumably would be used as a teaching facility. This factor could compromise the validity because the nurses and doctors caring for the patients may not have as much experience as medical personnel in other facilities not related to university studies.

The implemented design was to ensure that the validity of the study would be maintained to the highest degree possible. Two facilities were used during the study, a 900 unit university medical center and a 230 bed community hospital. Three criteria were incorporated into the study's design. The criteria included "employment of a mix of RN's, LPN's and UAP's, an average LOS greater than 2 days, and an average daily census of more than 80% of capacity" (pg. 157).

According to the study, these criteria were chosen to "ensure variability of staffing levels, as well as to guarantee adequate sample size during the study timeframe" (pg. 157).

The study's design seemed to be appropriate in that quantitative measures to determine levels of staffing as compared to deviation of length of stay would likely be much more specific and verifiable than a qualitative study seeking to determine the same thing.