HiSLAC is an independent, professionally-led study which will evaluate a key component of NHS England's policy drive for 7-day services: the intensity of specialist-led care of emergency medical admissions, with a particular focus on weekend provision. This research is important for patients and for NHS strategy because it offers a unique opportunity to evaluate the impact of the transition to seven-day working, and to understand factors likely to impede or enhance the effectiveness of this change in practice.

In addition to examining the impact on patient-centred outcomes, the project will also undertake a health economics analysis of the impact of increasing specialist provision across the NHS. HiSLAC will therefore provide useful information across the NHS about the cost-effectiveness of investing in consultant and other specialist staffing in implementing the drive to 7-day service provision.

In this survey instrument, physician characteristics and psychological attitudes have been shown to influence medical decisions. This study aims to describe the influence of several patient characteristics and reviewer characteristics and attitudes on the physician's overall case note review care quality judgement using an analytical method called multi-level modelling.

The investigators describe here a protocol for comparing quality of care given to patients admitted as emergencies to 20 hospital Trusts at weekends and on weekdays during two epochs, representing periods before (2012-2013) and during (2016-2017) the implementation of NHS England's 7-day services standards.

Using retrospective review of case records from 20 hospital Trusts during two time epochs, this study aims to determine whether there is a difference in quality of care offered to patients undergoing emergency admission (EA) to hospital at weekends compared with weekdays.

The main objectives are as follows:

1. To compare rates of errors and differences in care quality between weekend and weekday admissions,
2. To examine prevalent error types for weekend and weekday admissions,
3. If a difference in error rates or care quality between weekend and weekday admissions is found, examine whether the difference has changed between the two epochs.
4. To inform the Bayesian model proposed in this parallel health economics model. The co-primary outcomes are the weekend:weekday error rate ratio and the global assessment of care quality. The error rate is calculated as the number of errors per case record from admission to discharge or to 7 days, whichever occurs first.

Secondary outcomes include a comparison of weekend-weekday admissions in error typology and error-related adverse events (AEs), of error rates by day of the week within each admission group and correlation of weekend: weekday error rate ratios with weekend:weekday differences in specialist hours per 10 EAs.

In this survey instrument, physician characteristics and psychological attitudes have shown to influence medical decisions. The case note review process of determining the overall care quality is a type of medical decision. The HiSLAC study gives us an opportunity to determine whether patient or physician characteristics and physician attitudinal scores (physician aversion to ambiguity, need for cognition and personal need for structure) influence the overall care quality judgement during case note review. The investigators develop a case for considering this question with a multi-level model assuming the clustering within patient and within reviewers; furthermore, the investigators develop pre-specified hypotheses for testing. (See hypotheses) Our outputs from this are intended to inform better practice with case note reviews.

HYPOTHESES

For each objective a general hypothesis is provided:

Null hypothesis 1: To assess whether there is no significant relationship between patient case note characteristics and the physician's overall care quality judgements.

Null hypothesis 2: To assess whether there is no significant relationship between case note reviewer characteristics and their overall care quality judgements.

Null hypothesis 3. To assess whether there is no significant relationship between case note reviewer attitudes and their overall care quality judgements.

In addition to the above two objectives, one secondary objective is to assess the same effects of characteristics and attitudes on reviewer confidence in their care quality judgement. A further secondary objective is to assess whether there is a significant relationship between case-specific factors and reviewers' self-assessed confidence in their global care quality judgements.

Inclusion Criteria:

• case note reviewer involved in the HiSLAC study (including those partly reviewing their apportioned cases.)

Exclusion Criteria:

• participants not involved at the outset or at any point during the HiSLAC case note reviews

The plan is to share the information once the data has been collected and cleaned. Researchers will be contacted to determine the next steps to be taken with the data. Analysis will occur and this will be shared with participants and researchers alike.