Charging for intensive care using direct nursing hours as the cost marker.

The hypothesis that direct nursing hours correlate with the cost of a patient stay in intensive care was tested. One hundred and thirty-nine patients were studied and the data collected included: (a) direct nursing hours applied to each patient; (b) a daily TISS score: (c) a detailed costing of each patient (all costs are shown in N.Z.$). There was a strong correlation between the direct nursing hours and the total cost per patient (r2 = 0.98) (total cost = 54 x direct nursing hours + 344). Also a strong correlation existed between the total TISS scores and the total costs per patient (r2 = 0.96) (total cost = 67.13 x TISS). Direct nursing hours offer a relatively simple and logical method of allocating costs per patient.