MOH info about 'prefunding': https://www.moh.gov.sg/content/moh_web/home/pressRoom/Media_Forums/2013/role-of-pre-funding-.html
Because medishield-life (as well as eldershield / CareShield-Life) are all designed predicated upon the concept of 'pre-funding', policies have been in place such as
1) 30% surcharge for non medishield members for 10yrs upon introduction of new compulsory medishield-life scheme.
2) Claw back of all unpaid medishield-life premiums (subject to compound 4% annual interest) for Singaporeans returning to reside in Singapore who had previously been given waiver of premiums because they declared plans to permanently reside outside of Singapore.
From https://www.moh.gov.sg/content/moh_web/medishield-life/resources---faqs/faqs.html#anchorName :
Cessation of Suspension of Premium Collection
1. Under what circumstances would I be required to pay the accumulated sum of premiums suspended from collection with compound interest?
You would only have to pay the accumulated sum of premiums suspended from collection with compound interest if (a) you choose to relocate back to Singapore, (b) no longer meet the eligibility criteria for suspension of premium collection, or (c) choose to claim and benefit from MediShield Life payouts. Once this happens, your suspension of MediShield Life premium collection will cease and you will have to pay the full sum of premiums suspended from collection, with compound interest.
2. What is the interest rate used to calculate the amount of premiums I have to pay if I choose to relocate back to Singapore?
The interest rate is currently 4% per year and will be subject to applicable laws as may be amended from time to time. Interest will be imposed and computed on a compounded basis on full insurance periods that have passed.
According to MOH, medishield-life charges higher premiums to young members according to the concept of 'prefunding' so that premiums paid in later years can be more affordable and that to be fair, if the fund later ballooned due to prefunding being excessive, then premium rebates and refunds will be given to every Singaporean (since this is a compulsory scheme)
However, nowhere on the MOH website can it be found that a foreigner accepting Singapore PR/citizenship also has to contribute to the prefunding like those who joined earlier (which he had failed to contribute to before his PR/citizenship began) despite medishield-life providing such healthcare benefits to the new PR/ citizen for life. There is also no mention on MOH website about new PR/Citizens having to undergo medical checkups to see if they had pre-existing medical conditions which might entail hefty healthcare costs and thus entail the usual 30% medishield-life premium surcharge for 10yrs before normalizing thereafter.
Perhaps to be fair to existing Singaporeans who have paid compulsory, 'pre-funded' medishield-life premiums, the level of prefunding can be ascertained based on the annual age group specific, per capita pro-rated insurance loss ratio such that data about what has been unpaid out as claims and channeled to the main insurance fund on an annualized per capita basis according to age group can be later retrieved and charged to the new PR/citizen wannabe so that new PR/citizens can also contribute their fair share and do not shortchange existing Singaporeans when joining the national medishield-life scheme.
Ditto, Singaporeans who have previously opted out of the medishield-life scheme should only compensate for the 'prefunded' portion of medishield-life and not the full premium because they did not reside in Singapore (<140days /5yr duration) nor make any medishield-life healthcare claims as according to the medishield-life waiver from participation conditions that they have to adhere to.
What is sauce for the goose is sauce for the gander as well. Existing Singaporeans both at home and abroad should not be treated worst or have to also prefund the healthcare costs of foreigners who apply for new PR/ citizenship in Singapore.
(Likewise to be fair to the PRs, Singapore should REFUND to them the unused 'prefund' portion of medishield-life should their PR not be extended due to their option of returning back home).