Aviva has enhanced definitions for seven critical illness conditions and added a new additional benefit, to increase the number of claims paid.
Definitions have been enhanced for Alzheimer's disease, blindness, deafness, intensive care, multiple sclerosis and Parkinson's disease.
The enhancements vary according to the condition, but include extending cover to the end of the policy's term for Alzheimer's disease and Parkinson's disease (previously ended at age 65.)
Aviva has also widened the multiple sclerosis definition to enable payment on diagnosis, instead of requiring three months of continuous symptoms.
Ulcerative colitis has also been added as an additional benefit, while carcinoma in situ of the breast - also an additional benefit - has been enhanced, removing an exclusion for lobular carcinoma in situ.
Additional benefits mean that customers receive a payment of up to £25,000 while the policy continues in force and the sum assured is unaffected.
The enhancements apply to new critical illness policies taken out from 31st July 2015.
The changes have been introduced ahead of the December 2015 deadline for implementation of the ABI's statement of best practice for critical illness insurance.
Robert Morrison, chief underwriter for Aviva says: "It's our number one priority to make sure we pay as many claims as possible, so we're continually looking at our claims records to understand where claims have not been paid and the reasons why. We've enhanced cover across a range of conditions, widening our definitions so more claims can be accepted.
"We also found that in some instances we were more likely to pay claims than our policy wording might have suggested, so we have made some updates to reflect our claims philosophy more accurately. We've also revised the descriptions of some conditions, so it's clearer to customers what will be considered during a claim, and they can know exactly what to expect, making for a better customer journey all round."
The changes mean that 56 conditions are covered under Aviva's critical insurance policies, including 11 additional benefits. The number of ABI + definitions* has increased to 19.
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