SIMPLIFIED THERAPEUTIC INTERVENTION SCORING SYSTEM - THE TISS-28 ITEMS - RESULTS FROM A MULTICENTER STUDY

Objectives: To validate a simplified version of the Therapeutic Interv ention Scoring System, the TISS-28, and to determine the association o f TISS-28 with the time spent on scored and nonscored nursing activiti es. Design: Prospective, multicenter study. Setting: Twenty-two adult medical, surgical, and general Dutch intensive care units (ICUs). Pati ents: A total of 903 patients consecutively admitted to the ICUs. Inte rventions: TISS-28 was constructed from a random sample of 10,000 reco rds of TISS-76 items. The respective weights were calculated using mul tivariable regression analysis through the origin; TISS-76 scores were used as predicted values. Cross validation was performed in another r andom sample of 10,000 records and the scores of TISS-76 were compared with those scores obtained with TISS-28 (r = .96, r(2) = .93). Nursin g activities in the ICU were inventoried and divided into six categori es: a) activities in TISS-28; b) patient care activities not in TISS-2 8; c) indirect patient care (activities related to but not in direct c ontact with the patient, such as contact with family, maintaining supp lies); d) organizational activities (e.g., meetings, trainee supervisi on, research); e) personal activities (for the nurse him/herself, such as taking a break, going to the bathroom); f) other. During a 1-month period, TISS-76 and TISS-28 scores were determined daily from the pat ient's records by independent raters. During a 1-wk period, all of the nurses on duty scored their activities using a method called ''work s ampling.'' Measurements and Main Results: The analysis of validation i ncluded 1,820 valid pairs of TISS-76 and TISS-28 records. The mean val ue of TISS-28 (28.8 +/- 11.1) was higher (p < .00) than that value of TISS-76 (24.2 +/- 10.2). TISS-28 explained 86% of the variation in TIS S-76 (r = .93, r(2) = .86). ''Work sampling'' generated 10,079 registr ations of nursing activities, of which 5,530 could be matched with TIS S-28 records. Samples were taken from medical (19.3%), surgical (19.1% ), and general (61.6%) ICUs. Of these samples, 51.1% originated from u niversity hospitals, 35.8% from hospitals with >500 beds, 7.1% from ho spitals with 300 to 500 beds, and 5.8% from hospitals with <300 beds. Samples were scored in the morning (43.0%), evening (32.9%), and night shifts (24.1%). This sample of work activities was divided into four groups, according to their matched TISS scores (0 to 20, 20 to 35, 35 to 60, and >60 points). In the successive groups of TISS scores, there was a significant increase in the proportion of time spent on the act ivities scored with TISS-28. In the lower TISS score group (0 to 20 po ints), there was a significantly larger proportion of time allocated t o patient care activities not in TISS-28. There was no significant dif ference in the proportion of time spent when associating indirect pati ent care and organizational activities with the level of TISS score. T here was a significant decrease in the proportion of time spent on per sonal activities in the successive groups of TISS scores. The mean tim e spent per shift with personal activities varied between 1 hr and 40 mins (group 0 to 20 points TISS), and 1 hr and 16 mins (group >60 poin ts TISS). Significantly more time was used for patient care activities during the evening shift than during the day or the night shift. Conv ersely, nurses spent significantly less time on activities regarding t heir personal care during the evening shift. The time consumed for the activities of indirect patient care did not differ significantly amon g the three shifts. A typical nurse was capable of delivering work equ al to 46.35 TISS-28 points per shift (one TISS-28 point equals 10.6 mi ns of each nurse's shift). Conclusions: The simplified TISS-28 explain s 86% of the variation in TISS-76 and can therefore replace the origin al version in the clinical practice in the ICU. Per shift, a typical n urse is capable of delivering nursing activities equal to 46 TISS-28 p oints. This information, together with the information concerning the association of TISS score with the time spent in the various nursing a ctivities within the ICU, is relevant to the management of nursing man power in the ICU.