Does increasing the size of bi-weekly samples of records influence results when using the Global Trigger Tool? An observational study of retrospective record reviews of two different sample sizes

Source at http://dx.doi.org/10.1136/bmjopen-2015-010700.Objectives - To investigate the impact of increasing sample of records reviewed bi-weekly with the Global Trigger Tool method to identify adverse events in hospitalised patients. Design - Retrospective observational study. Setting - A Norwegian 524-bed general hospital trust. Participants - 1920 medical records selected from 1 January to 31 December 2010. Primary outcomes - Rate, type and severity of adverse events identified in two different samples sizes of records selected as 10 and 70 records, bi-weekly. Results - In the large sample, 1.45 (95% CI 1.07 to 1.97) times more adverse events per 1000 patient days (39.3 adverse events/1000 patient days) were identified than in the small sample (27.2 adverse events/1000 patient days). Hospital-acquired infections were the most common category of adverse events in both the samples, and the distributions of the other categories of adverse events did not differ significantly between the samples. The distribution of severity level of adverse events did not differ between the samples. Conclusions - The findings suggest that while the distribution of categories and severity are not dependent on the sample size, the rate of adverse events is. Further studies are needed to conclude if the optimal sample size may need to be adjusted based on the hospital size in order to detect a more accurate rate of adverse events

Identifying and measuring patient harms. A study of measuring adverse events in hospitalised patients by the Global Trigger Tool record review method

Patient harms, or adverse events which is the term used in this PhD thesis, is a global health problem. The Global Trigger Tool (GTT) is a widely used method to identify and measure adverse events (AEs). The method involves reviewers searching for triggers (situations) in randomly selected medical records and subsequently identifying AEs. However, the method is criticized due to the time used by reviewers, the sampling strategy and low agreement between review teams. The overall aim of this PhD was to evaluate the effect of increasing the number of records to be reviewed, changes of reviewers and the use of automatic versus manual trigger identification in the GTT. This was investigated in order to improve the validity and reliability of the GTT, and to increase the efficiency of the method by reducing the personnel time required to identify AEs. The results showed that increasing the sample size seven times increased the precision of the results as the confidence interval is narrower than in a smaller samples size. In a large sample a higher rate of adverse events was identified than in a small sample. Keeping at least one reviewer consistent increased the agreement of the identified AEs. The use of automatic trigger identification identified the same rate of AEs as with the use of manual trigger identification, and was time efficient. These adjustments increase the validity and reliability of the GTT and reduce the review time and resources used

Contribution of adverse events to death of hospitalised patients

Background - There is no standardised method to investigate death as a patient safety indicator and we need valid and reliable measurements to use adverse events contributing to death as a quality measure. Objective - To investigate the contribution of severe adverse events to death in hospitalised patients and clarify methodological differences using the Global Trigger Tool method on all inpatient deaths compared with a sample of general hospitalised patients. Method - Retrospective records reviewing using the Global Trigger Tool method. Results - In 0.3% of hospital admissions, adverse events contribute to inpatient death. Patients who die in hospital have twice the rate of adverse events per 1000 patient days compared with general patients, 76.7 vs 36.5 (p Conclusions - Patients dying in hospitals experience seven times the rate of severe adverse events. Reviewing all inpatient death by the Global Trigger Tool method discloses new valid and reliable data of severe adverse events contributing to death which otherwise would be undetected

Is a modified Global Trigger Tool method using automatic trigger identification valid when measuring adverse events? A comparison of review methods using automatic and manual trigger identification

Objectives - To evaluate a modified Global Trigger Tool (GTT) method with manual review of automatic triggered records to measure adverse events. Design - A cross-sectional study was performed using the original GTT method as gold standard compared to a modified GTT method. Setting - Medium size hospital trust in Northern Norway. Participants - One thousand two hundred thirty-three records selected between March and December 2013. Main outcome measure - Records with triggers, adverse events and number of adverse events identified. Recall (sensitivity), precision (positive predictive value), specificity and Cohen’s kappa with 95 % confidence interval were calculated. Results - Both methods identified 35 adverse events per 1000 patient days. The modified GTT method with manual review of 658 automatic triggered records identified adverse events (n = 214) in 189 records and the original GTT method identified adverse events (n = 216) in 186 records. One hundred and ten identical records were identified with adverse events by both methods. Recall, precision, specificity and reliability for records identified with adverse events were respectively 0.59, 0.58, 0.92 and 0.51 for the modified GTT method. The total manual review time in the modified GTT method was 23 h while the manual review time using the original GTT method was 411 h. Conclusions - The modified GTT method is as good as the original GTT method that complies with the GTTs aim monitoring the rate of adverse events. Resources saved by using the modified GTT method enable for increasing the sample size. The automatic trigger identification system may be developed to assess triggers in real-time to mitigate risk of adverse events

Is inter-rater reliability of Global Trigger Tool results altered when members of the review team are replaced?

Objective - To evaluate the inter-rater reliability of results from Global Trigger Tool (GTT) reviews when one of the three reviewers remains consistent, while one or two reviewers rotate. Design - Comparison of results from retrospective record review performed as a cross-sectional study with three review teams each consisting of two non-physicians and one physician; Team I (three consistent reviewers), Team II (one of the two non-physician reviewers or/and the physician from Team I are replaced for different review periods) and Team III (three consistent reviewers different from reviewers in Team I and Team II). Setting - Medium-sized hospital trust in Northern Norway. Participants - A total of 120 records were selected as biweekly samples of 10 from discharge lists between 1 July and 31 December 2010 for a 3-fold review. Intervention - Replacement of review team members was tested to assess impact on inter-rater reliability and adverse events measurment. Main Outcome Measure(s) - Inter-rater reliability assessed with the Cohen kappa coefficient between different teams regarding the presence and severity level of adverse events. Results - Substantial inter-rater reliability regarding the presence and severity level of adverse events was obtained between Teams I and II, while moderate inter-rater reliability was obtained between Teams I and III. Conclusions - Replacement of reviewers did not influence the results provided that one of the non-physician reviewers remains consistent. The experience of the consistent reviewer can result in continued consistency in interpretation with the new reviewer through discussion of events. These findings could encourage more hospital to rotate reviewers in order to optimize resources when using the GTT