Validation of the Hong Kong accident and emergency triage guidelines

Emergency Department Use Across Income Groups Following an Increase in Cost-Sharing

Importance

To encourage the appropriate utilization of emergency care, cost-sharing for emergency care was increased from HK$100 (US $12.8) to HK$180 (US $23.1) per visit in June 2017 in all public hospitals in Hong Kong. However, there are concerns that this increase could deter appropriate emergency department (ED) visits and be associated with income-related disparities.

Objective

To examine changes in ED visits after the fee increase.

Design, Setting, and Participants

This retrospective cohort study used administrative data from June 2015 to May 2019 from all public hospitals in Hong Kong. Participants included all Hong Kong residents aged 64 years and younger, categorized into low-income, middle-income, and high-income groups according to the median household income in their district of residence. Data analysis was performed from May to June 2023.

Main Outcomes and Measures

The primary outcome was the ED visit rate per 100 000 people per month, categorized into 3 severity levels (emergency, urgent, and nonurgent). Secondary outcomes include general outpatient (GOP) visit rate, emergency admission rate, and in-hospital mortality rate per month at public hospitals. Segmented regression analyses were used to estimate changes in the level and slope of outcome variables before and after the fee increase.

Results

This study included a total of 5 441 679 ED patients (2 606 332 male patients [47.9%]; 2 108 933 patients [38.5%] aged 45-64 years), with 2 930 662 patients (1 407 885 male patients [48.0%]; 1 111 804 patients [37.9%] aged 45-64 years) from the period before the fee increase. The fee increase was associated with an 8.0% (95% CI, 7.1%-9.0%) immediate reduction in ED visits after June 2017, including a 5.9% (95% CI, 3.3%-8.5%) reduction in urgent visits and an 8.9% (95% CI, 8.0%-9.8%) reduction in nonurgent visits. In addition, a 5.7% (95% CI, 4.7%-6.8%) reduction of emergency admissions was found, whereas no significant changes were observed in in-hospital mortality. Specifically, a statistically significant increase in GOP visits (4.1%; 95% CI, 0.9%-7.2%) was found within the low-income group, but this association became insignificant after controlling for the social security group, who were exempted from payment, as a control.

Conclusions and Relevance

In this cohort study, the fee increase was not associated with changes in ED visits for emergency conditions, but there was a negative and significant association with both urgent and nonurgent conditions across all income groups. Considering the marginal increase in public GOP services, further study is warranted to examine strategies to protect low-income people from avoiding necessary care.

Performance of a three-level triage scale in live triage encounters in an emergency department in Hong Kong

Background

Despite its continued use in many low-volume emergency departments (EDs), 3-level triage systems have not been extensively studied, especially on live triage cases. We have modified from the Australasian Triage Scale and developed a 3-level triage scale, and sought to evaluate its validity, reliability, and over- and under-triage rates in real patient encounters in our setting.

Method

This was a cross-sectional study in a single ED with 24,000 attendances per year. At triage, each patient was simultaneously assessed by a triage nurse, an adjudicator (the “criterion standard”), and a study nurse independently. Predictive validity was determined by comparing clinical outcomes, such as hospitalization, across triage levels. The discriminating performance of the triage tool in identifying patients requiring earlier medical attention was determined. Inter-observer reliability between the triage nurse and criterion standard, and across providers were determined using kappa statistics.

Results

In total, 453 triage ratings of 151 triage cases, involving 17 ED triage nurses and 57 nurse pairs, were analysed. The proportion of hospital admission significantly increased with a higher triage rating. The performance of the scale in identifying patients requiring earlier medical attention was as follows: sensitivity, 68.2% (95% CI 45.1–86.1%); specificity, 99.2% (95% CI 95.8–100%); positive predictive value, 93.8% (95% CI 67.6–99.1%); and negative predictive value, 94.8% (95% CI 90.8–97.1%). The over-triage and under-triage rates were 0.7% and 4.6%, respectively. Agreement between the triage nurse and criterion standard was substantial (quadratic-weighted kappa = 0.76, 95% CI, 0.60–0.92, p < 0.001), so was the agreement across nurses (quadratic-weighted kappa = 0.81, 95% CI 0.65–0.97, p < 0.001).

Conclusions

The 3-level triage system appears to have good validity and reasonable reliability in a low-volume ED setting. Further studies comparing 3-level and prevailing 5-level triage scales in live triage encounters and different ED settings are warranted.