When looking at group health schemes there is often confusion because, while some people argue that group plans are not allowed to exclude you from cover because of your current health or your previous medical history, other people maintain that they are permitted to refuse cover for pre-existing conditions.

The truth is that you cannot be refused membership of a group plan solely because of you current medical state, including any disability which you may have, or because of your past medical history.

However, employers and insurers are permitted to ask you if you have any pre-existing medical conditions on enrollment or, if you submit a claim during your first year of cover, to look back to establish whether you have any past history of the condition which is the subject of your claim.

Where a pre-existing condition is reported or unearthed the employer or insurance company cannot simply deny you cover under a group plan but is allowed to impose an exclusion period for cover of that particular pre-existing condition. Having said this, there are federal and state laws which regulate the exclusions which employers and insurers can place on their group schemes.

Group health schemes may not impose pre-existing condition exclusion periods on the basis of pregnancy or genetic information. In addition, exclusion periods are not permitted in the case of newborn babies, newly adopted children and children who are placed for adoption.

In general, pre-existing condition exclusion periods can only be imposed for conditions which are diagnosed within the 6 months prior to joining a group scheme and for which you have been given (or been recommended to have) treatment. This 6 month period is often called the 'look back' period.

Wherever a pre-existing condition exclusion period is imposed it cannot generally be longer than 12 months and you must be given credit for any previous continuous creditable coverage. In this case cover is classed as continuous as long as it is not interrupted by a break in excess of 63 consecutive days. Almost all government sponsored and private health coverage is classed as creditable and this will include such things as Medicare, individual health insurance, military health coverage, VA coverage, foreign national coverage, student health insurance, Medicaid, Indian health insurance and more.

When an employer requires a waiting period for employees to enter a scheme, or an HMO requires a similar affiliation period, these cannot be counted in calculating any break in continuous coverage. Further, pre-existing condition exclusion periods have to take account of the waiting or affiliation period with the pre-existing condition exclusion period starting on the first day of the waiting or affiliation period.

If you are moving from one group scheme to another then the administrator of the new plan is allowed to look at your previous plan to work out any credit entitlement towards a pre-existing condition exclusion period for your new plan. This may mean for instance that if the new plan offers cover which was not provided under the old plan then exclusion periods may be imposed for pre-existing conditions which were not previously covered but which are covered under the new plan.

One final point worth noting is that you have to be given appropriate written notice of any pre-existing condition exclusion period and the group scheme administrator is obliged to help you to obtain a certificate of creditable coverage from your previous plan if you wish him to do so.