By medical release – do you mean a medical authorization? If so, they use that to order copies of your medical bills and reports. They can’t settle an injury claim with out copies of the medical bills/reports.

If you missed work because of your injury – they need your employment info.

If you have PIP coverage, Medical Payments coverage or if the at fault person does not have high enough limits and you have to file under your policies Under-insured motorist coverage – your company would need this information.

If you are filing a claim against the other car’s liability coverage – that company needs this information.