Section 79. Records kept by hospitals, dispensaries or clinics, and sanatoria under section seventy of chapter one hundred and eleven shall be admissible, and records which the court finds are required to be kept by the laws of any other state or territory, or the District of Columbia, or by the laws and regulations of the United States of America pertaining to the department of national defense and the veterans administration, by hospitals, dispensaries or clinics, and sanatoria similarly conducted or operated or which, being incorporated, offer treatment free of charge, may be admitted by the court, in its discretion, as evidence in the courts of the commonwealth so far as such records relate to the treatment and medical history of such cases and the court may, in its discretion, admit copies of such records, if certified by the persons in custody thereof to be true and complete; but nothing therein contained shall be admissible as evidence which has reference to the question of liability. Copies of photographic or microphotographic records so kept by hospitals, dispensaries or clinics, or sanatoria, when duly certified by the person in charge of the hospital, dispensary or clinic, or sanatorium, shall be admitted in evidence equally with the original photographs or microphotographs.

A record kept by any hospital, dispensary or clinic, or sanatorium under section seventy of chapter one hundred and eleven which is required to be produced in court by any party shall be certified by the affidavit of the person in custody thereof to be a true and complete record, and shall be delivered by such hospital, dispensary or clinic, or sanatorium to the clerk of such court, who shall keep the same in his custody until its production is called for at the trial or hearing by the party requiring the said record. Such record, so certified and delivered shall be deemed to be sufficiently identified to be admissible in evidence if admissible in all other respects. The party requiring the production of said record and, in the discretion of the court, any other party may examine said record in the custody of the clerk at any time before it is produced in court. The clerk upon completion of such trial or hearing shall notify such hospital that said record is no longer required and will be returned to the hospital by certified mail unless an authorized representative of the hospital calls for the same at the office of said clerk within seven days of said notice.