Before travelling, you will receive your PDT HealthCert from your clinic. PDT HealthCert is digitally authenticated and endorsed by MOH (i.e. it is issued by a recognised medical facility and has not been tampered with). If you have presented your NRIC at the medical facility, the QR code will also be automatically uploaded onto your Singpass app.
When travelling abroad, the QR code can be shown to foreign travel authorities, who may scan the QR code with any reader (e.g. normal phone camera) to verify the authenticity of the digitally authenticated and endorsed PDT HealthCert.