# A Comprehensive Assessment of Cancer Patient Performance Status Documentation in a Large, Multicentre Hospital System

## TL;DR

This study found that performance status documentation for cancer patients in electronic health records is generally low and varies by cancer type and hospital, highlighting the need for improvement to better use real-world data.

## Contribution

The study introduces a high-accuracy RegEx method for automatically identifying performance status scores in diverse clinical documents.

## Key findings

- Only 35% of patients had a documented PS score within 90 days before or 365 days after their first cancer diagnosis code.
- PS documentation varied significantly by cancer type and hospital, with lung cancer having the highest odds of documentation.
- Patients with documented PS scores had poorer 1-year survival rates compared to those without.

## Abstract

The performance status (PS) is an indicator of a cancer patient's ability to perform everyday activities and plays a key role in oncology. Research suggests that the documentation of PS scores in electronic health records (EHR) is deficient.

We analysed PS score documentation (Karnofsky or ECOG/Zubrod/WHO) in the hospital, consultation, and multidisciplinary team meeting (MDT) records of patients newly referred for a cancer at a large, public, multisite hospital system, between 1 January 2019 and 1 June 2021. We developed a regular expression (RegEx) to automatically identify PS in documents and assessed what patient and hospital characteristics were associated with PS documentation.

Our RegEx achieved accuracy, and weighted‐ and macro‐average F1 score, > 0.95 for all document types. We included 68,479 patients. 35% had a documented PS between −90 and +365 days of their first ICD‐10 cancer code. 18% of MDT reports contained a PS score.

In multivariate analysis, without accounting for metastatic status at diagnosis, odds ratios (ORs) for PS documentation in patient files varied by cancer type, from 0.47 (95% confidence interval: [0.42; 0.52]) for genitourinary to 3.30 [3.00; 3.61] for lung cancer, and hospital, from 0.27 [0.23; 0.33] to 3.38 [3.14; 3.63]. Male patients were more likely to have a documented PS (OR = 1.08 [1.04; 1.13]), as well as older patients. The number of each type of document was positively correlated with the presence of a score. When adding metastatic status at diagnosis, the OR for metastatic status was large (3.29 [3.13; 3.46]), but associations with other covariates were not noticeably affected. Documented PS close to diagnosis was associated with poorer 1‐year survival (25% of patients with PS died within 1 year, vs 12% without PS).

PS score documentation was variable and generally low. Improved documentation is required if EHRs are to be used as a source of real‐world data.