# Causes and effects of hospital nursing shortages to consider potential feedback effects: an umbrella review

## TL;DR

This study reviews causes and effects of hospital nursing shortages, suggesting they may be self-reinforcing and urging early intervention.

## Contribution

The study introduces the concept of self-reinforcing feedback loops in nursing shortages and provides a testable hypothesis for early intervention.

## Key findings

- Nursing shortages are linked to both causes and effects that may reinforce each other.
- Early intervention is critical for nurse retention and healthcare resilience.
- Econometric analyses may be biased due to feedback effects in staffing shortages.

## Abstract

In Canada and internationally, health systems have experienced rising healthcare staffing shortages in recent years. Specifically, this study seeks to analyse evidence on the causes and effects of hospital nursing shortages, to consider whether shortages may be self-reinforcing. It complements an existing linear healthcare workforce logic model (Sonderegger et al., 2021) by considering whether there may be evidence that implies the existence of feedback loops (a form of system dynamics).

An umbrella review was undertaken to identify both causes and effects of hospital nursing shortages. A two-phase approach was undertaken: first, a review of all articles to identify a common list of factors, and second, a subsequent line-by-line review to ensure comprehensive coding.

The umbrella review identified several specific issues which were both causes and effects of nursing shortages, across a number of articles. This suggests that shortages could be self-reinforcing. For policymakers, the implication is that early intervention is likely to support the resilience and retention of hospital nurses. For researchers, this study highlights the risk of biased coefficients within econometric analysis and provides a testable cross-country hypothesis for the impacts of early intervention.

Overall, this study contributes to existing academic literature and practical policymaking by identifying evidence that nursing shortages may be self-reinforcing. Through proactive intervention to restrain the growth of workforce shortages, policymakers can support the welfare of healthcare service users and nurses themselves.

The online version contains supplementary material available at 10.1186/s12960-025-01028-w.