A research analysis carried out by Watson Wyatt Worldwide, a global consulting firm, has found that older workers without other health care insurance options are more likely to defer retirement to stay covered under their employer's plan.

It also found that other factors, such as whether an employee has a pension, also contribute to decisions on when to retire. Watson Wyatt analyzed data collected from 1992 to 2004 as part of the University of Michigan’s Health and Retirement Study, a biannual survey of 22,000 older US workers.

The analysis found that employees who rely on their employers for health care coverage and do not expect to receive employer-provided health benefits in retirement are 16.5 percentage points less likely to retire in any given year than workers with access to health care coverage through another source.

These sources can include a spouse’s health insurance plan, public health insurance, COBRA coverage or employer-sponsored retiree health insurance.

The analysis of workers over age 50 found that a number of factors, such as retirement types, public policies and household health, in addition to health care, influence retirement decisions.

Mark Warshawsky, director of retirement research at Watson Wyatt, said: The link between health care and retirement security is just one of the factors affecting older workers’ decisions about retirement. Most factors point to an aging workforce, driven by delayed retirements.