It is helpful, in undertaking the task of construction of s. 48, to have in mind the model provided by the innovative legislation in this field enacted by the Parliament of the United Kingdom in the Limitation Act 1963 ("the 1963 Act"). Section 1 of that Act provided that the period of three years prescribed by the Limitation Act 1939 UK for bringing a personal injuries action based on negligence, other breach of duty or nuisance (hereinafter collectively referred to as "negligence") shall not afford any defence to such an action provided, inter alia, that it was proved that the material facts relating to the cause of action were or included facts of a decisive character which were at all times outside the knowledge (actual or constructive) of the plaintiff until a date which satisfied the time prescriptions in the section. Section 7 was an interpretation section which, inter alia, elaborated in some detail the meaning that was to be given to "material facts", "facts of a decisive character" and "knowledge (actual or constructive) of a person". "Material facts" were defined exhaustively to refer to any one or more of (a) the fact that personal injuries resulted from the negligence constituting the cause of action, (b) the nature or extent of the personal injuries resulting from the negligence, and (c) the fact that or the extent to which the personal injuries or any of them were attributable to the negligence. Material facts relating to a cause of action were to be taken to have been "facts of a decisive character" if a reasonable person, knowing them and having obtained appropriate advice about them, would have regarded them as determining that an action would have a reasonable prospect of success resulting in an award of damages sufficient to justify bringing the action. A fact was to have been outside the "knowledge (actual or constructive) of a person" at any time only if he did not then know the fact and had taken all such action as was reasonable for him to have taken in order to ascertain it, including, in some cases, obtaining appropriate advice. The Limitation Act 1975 UK repealed these provisions and inserted fresh provisions in the Limitation Act 1939. It is unnecessary to detail those provisions for present purposes since the South Australian legislation was enacted whilst the 1963 Act was in force.