The utility of multidimensional ED overcrowding scale and modified national emergency department overcrowding scale to assess ED crowding: a prospective pilot study

Abstract

Objective To establish a practicable and balanced emergency department overcrowding (EDO) assessment system suitable for domestic application in Chinese ED setting. Methods The factors that might affect EDO were evaluated by multiple linear regression analysis. The National Emergency Department Overcrowding Scale(NEDOCS) was modified(NEDOCSBJ). The database of factors which might affect EDO was founded and the Multidimensional ED Overcrowding Scale (MEDOS) items, including 9 objective and 3 subjective were screened. Simultaneously, the EDO assessment data pairs were collected three times a day (1: 00, 9: 00, 17: 00) for a period of 6 months. Consistency among the Visual Analogue Scale (VAS), NEDOCSBJ and MEDOS were checked by Bland-Altmann plot. Results The multiple linear regression was made with VAS (average value of VAS-physician and VAS-nurse) as outcome variable, Pbed/Bt, Xn, Wtime and ABI as independent variable. The modified NEDOCS (NEDOCSBJ) model was established: NEDOCSBJ=83.563×(Pbed/Bt)+ 7.201×(Xn)+ 0.116×Wtime+ 0.302×ABI+ 2.835. It was shown that the average value of MEDOS was 25.4 ± 5.8(n=552, 5-39). The correlation analysis showed that MEDOS correlates with VAS (r=0.664, P<0.01) and NEDOCSBJ (r=0.939, P<0.01) significantly. Intra-class correlation coefficients (ICC) between NEDOCSBJ and MEDOS, as well as Bland-Altman plot (95% limits of agreement: -6.74, 30.66), was fairly acceptable, which meant the consistency between the two methods. Conclusions It seems that modified NEDOCS (NEDOCSBJ) model has potential value for EDO evaluation, yet it is less practical in emergency environment since it is difficulties to oBtain the primary data, which need advanced patient information track system. MEDOS seems to a promising EDO evaluation method not only because it is intuitive, ready to evaluate, but also because of the availability and good proportionality and balance of the data. Key words: Emergency Department; Crowding; The National Emergency Department Overcrowding Scale; Visual Analogue Scale; Multidimensional ED Overcrowding Scale; Methodology; Bland-Altman plot