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What Must Be Reported

Adverse event reporting obligations for medical device MAHs are established in PMD Act Article 68-2 and the associated Ministerial Ordinance on Safety Measures for Medical Devices. These set out what must be reported, to whom, and within what timelines.

Reportable adverse events — overview​

Japan's adverse event reporting system for medical devices requires MAHs to report to MHLW when:

  1. A patient died and there is reasonable possibility the device contributed
  2. A patient suffered a serious injury and there is reasonable possibility the device contributed. "Serious injury" includes:
    • Life-threatening situations
    • Permanent impairment of a body function or permanent damage to a body structure
    • Condition requiring medical or surgical intervention to prevent permanent impairment
    • Hospitalisation or prolonged hospitalisation
    • Any condition considered serious by a physician
  3. A malfunction occurred that, if it were to recur, would likely cause a death or serious injury
  4. An infection was transmitted by the device

Serious injury and death reports​

For death or serious injury reports, the MAH must:

  • Report to MHLW within 15 calendar days (for events where there is reasonable possibility of device causation)
  • Include: device description, event description, patient details, investigation status, and initial assessment of causation
  • Submit a follow-up report once the investigation is complete if new information becomes available

Malfunction reports​

For device malfunctions (without associated death or serious injury but with potential to cause harm if recurring):

  • Report to MHLW within 30 calendar days
  • Include: device description, nature of malfunction, number of units affected, and corrective actions taken or planned

Overseas adverse events​

MAHs must also report adverse events that occur overseas involving the same device when:

  • The event would be reportable if it occurred in Japan
  • The event may have implications for Japanese patients

MHLW has specific guidance on the reporting timelines for overseas events (generally 15 or 30 days from the MAH becoming aware of the overseas event).