De. Kim et Dr. Berlowitz, THE LIMITED VALUE OF ROUTINE LABORATORY ASSESSMENTS IN SEVERELY IMPAIRED NURSING-HOME RESIDENTS, JAMA, the journal of the American Medical Association, 272(18), 1994, pp. 1447-1452
Objective.-To determine the usefulness of a routine, comprehensive bat
tery of laboratory tests in a severely impaired elderly nursing home p
opulation. Design.-Prospective observational survey. Setting.-Skilled
nursing facility wards of a geriatric and extended care veterans hospi
tal. Patients.-Consecutive sample of 108 veterans with severe cognitiv
e and functional impairments, who had been hospitalized at least 6 mon
ths. Main Outcome Measures.-Proportions of tests categorized as screen
ing, monitoring, follow-up, or diagnostic; frequency of abnormal test
results, interventions warranted and performed on the basis of these a
bnormalities, and beneficial or adverse effects. Results.-Of 6771 indi
vidual nondiagnostic tests performed, 17.2% yielded abnormal results;
of these, 33.3% were new. However, only 0.2% of tests resulted in pati
ent benefit. Of 989 panels performed, 31.0% contained at least one abn
ormality, but only 1.0% of panels (10 patients) yielded any benefit. O
verall usefulness was related to the purpose of the testing, with 31.5
% of screening tests yielding abnormalities, compared with 45.5%, 78.2
%, and 68.7% of monitoring, follow-up, and diagnostic panels, respecti
vely (P<.05 for each compared with screening panels). None of the scre
ening panels detected an abnormality that led to patient benefit, comp
ared with 1.0%, 1.4%, and 3.0% of monitoring, follow-up, and diagnosti
c panels. Conclusions.-Routine comprehensive laboratory panels may not
be warranted in the most severely impaired elderly patients in long-t
erm care settings. Discontinuing true screening tests and limiting tes
ting strictly to monitoring, followup, or diagnostic purposes could mi
nimize the costs of laboratory assessment without losing its potential
benefits.