Question
Are there other countries than Chile where private institutions and government alike require people to sign a debt acknowledgement with date and amount in blank (sometimes validated at the notary), to be filled some time after the signing?
Related: I posted a distinct but similar question on https://academia.stackexchange.com/questions/193376/research-funding-conditionned-to-the-signing-of-a-debt-acknowledgment-with-amoun about such debt acknowledgments used as a prerequisite for researchers to receive state research funding.
Context
In Chile, private hospitals routinely require their clients to sign a debt acknowledgment with an amount in blank before being admitted to the emergencies. It is considered as a (desirable) way to speed-up the admission process, permitting to people in pain to skip a long administrative process in order to insure that the cost of their medical treatment will be covered.
The institution distributing state research funding ANID (formerly known as CONICYT) via various "Fondecyt" competitions ("Fondecyt Initiation" for young researchers, "Fondecyt Regular" for other researchers, etc.) is doing the same, requesting researchers who "won" the competition to sign at a notary's office a debt acknowledgment with both the amount and the date in blank, as a condition to get access to the research funding. Only a few notaries accept to validate such documents, but only because they normally compute their fees for validating such a document based on a percentage of the amount of the debt acknowledgment (which they cannot do when the amount is left blank).
Motivation
I thought that this would be illegal: signing a document is supposed to mean that one has read the terms of the documents and agrees with them, which is of course does not mean that one will agree with the terms of the documents once it has been modified. I was told that such document was indeed legal in Chile.
As an academic in Chile, I am expected to apply for state research funding, and to sign such debt acknowledgment if awarded such funding (and told "not to worry, as such debt acknowledgment is never enforced by the government"). I find this the most note worthy example of systemic corruption, in the sense that the very meaning of a signed contract is corrupted. I would like to gather arguments in order to try to convince higher instances of the inadequacy of such a policy.