Chapter 5. Overall Results
2009 Comparative Database Results
Reporting the average across hospitals ensures that each hospital receives an equal weight that contributes to the overall average. Reporting the data at the hospital level in this way is important because culture is considered to be a group of hospital characteristics and is not considered to be a solely individual characteristic. An alternative method would be to report a straight percentage of positive responses across all respondents, but this method would give greater weight to respondents from larger hospitals. There are almost twice as many respondents from larger hospitals as those from smaller hospitals (as noted in Chapter 3).
Calculation of Percent Positive Scores
Most of the survey's items ask respondents to answer using 5-point response categories in terms of agreement (Strongly agree, Agree, Neither, Disagree, Strongly disagree) or frequency (Always, Most of the time, Sometimes, Rarely, Never). Three of the 12 patient safety culture composites use the frequency response option (Feedback and Communication About Error, Communication Openness, and Frequency of Events Reported) while the other nine composites use the agreement response option
Item-Level Percent Positive Response
Both positively worded items (such as "People support one another in this work area") and negatively worded items (such as "We have patient safety problems in this work area") are included in the survey. Calculating the percent positive response on an item is different for positively and negatively worded items:
- For positively worded items, percent positive response is the combined percentage of respondents within a hospital who answered "Strongly agree" or "Agree," or "Always" or "Most of the time," depending on the response categories used for the item.
For example, for the item "People support one another in this work area," if 50 percent of respondents within a hospital Strongly agree and 25 percent Agree, the item-level percent positive response for that hospital would be 50% + 25% = 75% positive.
- For negatively worded items, percent positive response is the combined percentage of respondents within a hospital who answered "Strongly disagree" or "Disagree," or "Never" or "Rarely," since a negative answer on a negatively worded item indicates a positive response.
For example, for the item "We have patient safety problems in this work area," if 60 percent of respondents within a hospital Strongly disagree and 20 percent Disagree, the item-level percent positive response would be 80 percent positive (i.e., 80 percent of respondents do not believe they have patient safety problems in their work area).
Composite-Level Percent Positive Response
The survey's 42 items measure 12 areas or composites of patient safety culture. Each of the 12 patient safety culture composites includes 3 or 4 survey items. Composite scores were calculated for each hospital by averaging the percent positive response on the items within a composite. For example, for a 3-item composite, if the item-level percent positive responses were 50 percent, 55 percent, and 60 percent, the hospital's composite-level percent positive response would be the average of these three percentages or 55% positive.3
Overall Results: Composite and Item-Level Charts
The composite-level results in Chart 5-1 show the average percent positive response for each of the 12 patient safety culture composites, across all hospitals in the database. By displaying the percent positive as an average across hospitals, each hospital's composite score is weighted equally. The patient safety culture composites are shown in order from the highest average percent positive response to the lowest.
Teamwork Within Units. the extent to which staff support one another, treat each other with respect, and work together as a team. This area was the patient safety culture composite with the highest average percent positive response (79 percent), indicating it is an area of strength across the database hospitals (Chart 5-1).
Nonpunitive Response to Error. the extent to which staff feel that event reports and their own mistakes are not held against them and that mistakes are not kept in their personnel file. This area was the patient safety culture composite with the lowest average percent positive response (44 percent), indicating it is an area with potential for improvement across the database hospitals (Chart 5-1).
Handoffs and Transitions—the extent to which important patient care information is transferred across hospital units and during shift changes. This area was the other patient safety culture composite with the lowest average percent positive response (44 percent), indicating it is also an area with potential for improvement for most hospitals (Chart 5-1).
The item-level results in Chart 5-2 show the average percent positive response for each of the 42 survey items. The survey items are grouped by the patient safety culture composite they are intended to measure. Within each composite, the items are presented in the order in which they appear in the survey. The survey item with the highest average percent positive response (86 percent) was from the patient safety culture composite Teamwork Within Units: "When a lot of work needs to be done quickly, we work together as a team to get the work done." The survey item with the lowest average percent positive response (35 percent) was from the patient safety culture composite Nonpunitive Response to Error: "Staff worry that mistakes they make are kept in their personnel file," (that is, an average of only 35 percent of respondents in each hospital Strongly disagreed or Disagreed with this negatively worded item).
Results from the item that asked respondents to give their hospital work area/unit an overall grade on patient safety are shown in Chart 5-3. The chart shows the average percentage of respondents within each hospital providing grades from "A-Excellent" to "E-Failing." On average across hospitals, most respondents were positive with 73 percent giving their work area or unit a patient safety grade of "A-Excellent" (25 percent) or "B-Very Good" (48 percent). Very few (5 percent) gave their work area/unit a "Poor" (4 percent) or "Failing" (1 percent) grade.
Results from the item that asked respondents to indicate the number of events they had reported over the past 12 months are shown in Chart 5-4. The chart shows the average percentage of respondents within each hospital who indicated that they reported "No event reports" up to "21 or more event reports." On average across hospitals, most respondents (52 percent) reported no events in their hospital over the past 12 months. Underreporting is likely. Event reporting was probably identified as an area for improvement for most hospitals because potential patient safety problems may not be recognized or identified and therefore may not be addressed.
3 Note that this method for calculating composite scores is slightly different than the method described in the September 2004 Survey User's Guide that is part of the original survey toolkit materials on the AHRQ Web site. The guide advises computing composites by calculating the overall percent positive across all the items within a composite. The updated recommendation included in this report is to compute item percent positive scores first, and then average the item percent positive scores to obtain the composite score, which gives equal weight to each item in a composite. The Survey User's Guide will eventually be updated to reflect this slight change in methodology.