Marga Hoogendoorn

142 since its launch. Different nurses in different hospitals were followed by observers. Time- and-motion techniques were used to measure the nursing time spend on a patient for all nursing activities during day-, evening and night shifts. The original NAS-points were converted to the predefined time and compared with the observed time. The correlation found between the total converted NAS time and the total observed time per patient was 59%. This indicates that the NAS only explains 59% of the nursing time. The converted NAS time per patient was higher compared with the observed time, which indicates that the NAS overestimated the total needed nursing time. For a more effective nursing capacity planning it is therefore advised to gain better insight into the true nursing workload and revise the time weights to each NAS-item. Chapter 4 describes the results of a study to assess the association between the objective nursing workload and the perceived nursing workload and to identify other factors associated with the perceived nursing workload. During 228 shifts in eight different hospitals the objective nursing workload was measured with the NAS and the perceived nursing workload with the NASA-TLX. Clinical researchers identified other factors based on literature and data available in the Dutch national quality registry for Intensive Care and categorized those factors in three categories: patient factors (severity of illness, comorbidities, age, BMI and planned or unplanned admission), nursing factors (educational level) and contextual factors (number of patients per nurse, type of shift and day of admission or discharge). This study showed that workload is perceived differently by nurses compared to the objective nursing workload as measured with NAS; the NAS was not significantly associated with the perceived nursing workload. However, both the severity of illness of the patient and being a student nurse were factors that increase the perceived nursing workload. Planning of nursing staff should therefore be based on the NAS, the severity of patient illness and the graduation level of the nurse. Chapter 5 focuses on the association of the objective and perceived nursing workload with the workload satisfaction of ICU nurses. The hypothesis in this study was that both a too low or too high workload could lead to dissatisfaction of the nurse about the nursing workload. We measured both the objective nursing workload with NAS and the perceived nursing workload with NASA-TLX in 226 different shifts in eight different hospitals and asked the nurse at the end of each shift to rate their satisfaction about their workload on a scale from 0 (not satisfied at all) till 10 (very satisfied). This study showed that a NAS-score around 80 points per nurse leads to a significant higher chance of a nurse being satisfied. Furthermore, a high perceived nursing workload with NASA-TLX leads to a significant higher chance of a nurse being satisfied. A further increase of both the objective and perceived nursing workload to a very high or a low workload diminish these