In developed countries serious childhood illness is uncommon but increasing numbers of families seek urgent face-to-face medical assessment [
The Paediatric Observation Priority Score (POPS) is a method of identifying the range of severity of childhood illness, to support staff in taking the decision to redirect the child to primary care or discharge to self-care and to help them in expediting senior/specialist assistance for deteriorating children [
POPS uses a combination of physiological, behavioural, and known-risk parameters to generate a score of either 0, 1, or 2 (Figure
Candidate items evaluated for POPS. Paediatric Observation Priority Score (POPS) Chart. This chart is not a substitute for good clinical judgement and any concerns about the condition of a child should be brought to the attention of a senior nurse or doctor. POPS is copyrighted (creative commons attribution noncommercial share-alike 4.0), Dr. Damian Roland and Dr. Ffion Davies 2010. This is version 1.3, August 2016.
Scoring systems often perform less well outside the organisation that developed the score. This study aimed to validate how the POPS score performed in other EDs in the United Kingdom (UK).
The objectives of the study were to describe the distribution of scores in EDs outside our institution, confirm a threshold indicator of POPS > 4 for hospital admission risk (which was the threshold in local data), and examine discharge and representation rates following uptake of POPS. POPS was implemented in 4 EDs. The characteristics of each of the EDs is shown in Table
Patient disposition at individual hospital sites during study period.
Location (annual attendance of children to nearest 1000) | Successful ED discharge | Admitted < 24 hours or represented | Admitted > 24 hours | Total | ||||
---|---|---|---|---|---|---|---|---|
Hospital location | Bath (12000) | 122 | 52.4% | 75 | 32.2% | 36 | 15.5% |
|
Berkshire (26000) | 1034 | 60.2% | 364 | 21.2% | 321 | 18.7% |
|
|
Bristol (35000) | 702 | 72.1% | 110 | 11.3% | 170 | 17.5% |
|
|
Gloucestershire (15000) | 191 | 49.1% | 128 | 32.9% | 70 | 18.0% |
|
|
|
||||||||
Combined | 2049 | 61.7% | 677 | 20.4% | 597 | 18.0% |
|
All children (0–16 years) presenting to these departments were included on a convenience basis from February 2013 to June 2013. The department’s normal patient assessment/triage procedure was followed as per local protocol with the POPS observations being taken at the first available opportunity. National Standards in UK require an initial assessment of patients to occur within 15 minutes of arrival which all departments worked towards. A report form was used for prospective collection of each child’s POPS score (Figure
For the analysis patients were grouped into those that (a) were discharged from ED (including outpatient referrals) and who did not return within 7 days, (b) were admitted for less than 24 hours or represented within 7 days after discharge, and (c) were admitted to hospital for more than 24 hours. For validation of the admission threshold patients were separated into two groups based on an odds of admission calculated for the groups above and below a POPS of 4.
Ethical approval was granted via the East Midlands REC committee 2 and need for consent waived. Descriptive and statistical data were examined using SPSS v22.0.
Of 3338 patients submitted 15 were excluded (7 self-discharged and 8 unclear outcomes). The remaining patients are described in Table
Table of discharges and representations.
POPS | Successful discharge | Discharged but represented | Percentage represented |
---|---|---|---|
0 | 457 | 15 | 3.3 |
1 | 576 | 23 | 4.0 |
2 | 425 | 26 | 6.1 |
3 | 280 | 15 | 5.4 |
4 | 145 | 15 | 10.3 |
5 | 90 | 8 | 8.9 |
6 | 49 | 5 | 10.2 |
7 | 18 | 2 | 11.1 |
8 | 7 | 2 | 28.6 |
|
|
|
|
|
|||
Total | 2049 | 111 | 5.4 |
Relationship between readmission rate and POPS score on initial presentation.
Proportion of POPS at each site.
Disposition of patients presenting to 4 separate EDs, according to POPS.
In relation to threshold analysis across all centres, with POPS dichotomised into 0–4 and 5–11, odds ratio of admission was 5.13 (CI 4.06 to 6.49). Controlling for location there was no significant difference in the odds ratios for POPS 0–4 (
Odds ratio for admission at each site for POPS 5–11 against 0–4.
Location | Odds ratio for admission |
---|---|
Bath | 5.70 (CI 2.53 to 12.83) |
Berkshire | 7.28 (CI 5.01 to 10.57) |
Bristol | 3.95 (CI 2.64 to 5.91) |
Gloucestershire | 4.50 (CI 2.31 to 8.76) |
|
|
Combined | 5.13 (CI 4.06 to 6.49) |
This data demonstrates it is feasible to introduce POPS into EDs and maintain similar performance characteristics between sites. Across all sites POPS performed moderately well at predicting admission and safe discharge with similar characteristics to the site of derivation. Despite no specific education in the use of POPS, its performance was similar between sites with some expected variation due to different populations and size of units. Its performance, despite the absence of a well-defined, implementation strategy, would suggest it is a system that is relatively easy to implement successfully.
Unlike inpatient Early Warning Scores designed to detect deterioration, POPS has demonstrated an ability to aid detection of patients requiring hospitalisation in the ED safely, while also supporting discharge decision making for children with minor illness. The strong relationship between return rates and initial POPS allows a clinician or individual unit to define their own management thresholds, depending on their attitude to risk. It may be that children with intermediate POPS scores (3–6) would benefit from a mandated senior review prior to discharge, and identifying this middle group would assist each site in fine-tuning their discharge/admission threshold. At POPS above 4 in all the sites 30% of children were admitted for over 24 hours’ rate. An admission for over 24 hours infers that ongoing management was deemed necessary by the paediatric team and admission was unlikely to be related to any service or capacity pressures. While an individual score should never on its own determine the decision of a child these results support the use of a cut-off of around 4 as a decision making aid for admission and discharge. Senior clinicians could obviously make their own adjustments depending on local factors.
There are many potential benefits to wide scale implementation of this system aside from the rapid detection of critically unwell children. Potential cost savings include fewer referrals for inpatient treatment (current risk-averse practice results in overreferral), fewer serious adverse events (missed serious illness), and reducing numbers or costs of litigation claims. The combination of POPS with inpatient EWS is being investigated and will further enhance serious illness detection in the future (personal communication).
Although data was collected prospectively the time periods were not uniform between sites and there was no measure to determine standardisation of assessment between staff in a given Emergency Department. The ROC score remains low but comparable with other Paediatric Early Warning Scores used in children’s Emergency Departments [
We have demonstrated it is feasible to implement POPS into several EDs. This data can now be used to inform a formal prospective external validation study and assist in ongoing rollout to interested sites.
Dr. Roland and Dr. Davies own copyright to the Paediatric Observation Priority Score which is available via a creative commons attribution noncommercial share-alike 4.0 license.
The contribution of the Principal Investigators Dr. Elizabeth Gilby (Bath), Liza Keating (Reading), Mark Lyttle (Bristol), and Victoria Stacey (Gloucestershire) to the success of this study should be recognised. The initial contribution of Ashley Douglas to data amalgamation is also acknowledged and was recognised in an early abstract of this work (Roland D., Arshad F., Douglas A., et al. Spreading innovation in children’s emergency care: an external pragmatic validation of the paediatric observation priority score. Emerg Med J 2015; 32:978-979).