It is sobering to be confronted with the extent to which Scottish public services depend on IT systems.

When something goes badly wrong with a digital network, as it did at NHS Greater Glasgow and Clyde (NHSGGC) this week, the consequences are immediate and far-reaching. Chaos was averted when network servers controlling clinical and administrative systems failed, but 600 appointments, including 48 chemotherapy treatments, were still cancelled.

The most alarming aspect of this episode is the fact that, while the system had a back-up, that crucial back-up also failed.

The health board has apologised promptly to patients and Health Secretary Alex Neil has rightly ordered a review of IT systems and back-up arrangements across the Scottish NHS, a move which, in conjunction with the investigations into why the Glasgow system failed, will be aimed at helping prevent a repeat of the problem.

What of patients who have had their appointments cancelled, however? The majority of these have been people scheduled for outpatient appointments. Some will have waited months to see a specialist; some may be attending with complaints that could prove serious. Mr Neil has offered his reassurances that patients will be seen in "a reasonable period of time", though many will be wondering what that might mean. It would clearly be unacceptable for any patient to have to return to the end or near the end of a long waiting list because they missed their appointment due to this IT glitch. Mr Neil envisages that staff may have to work longer hours for a short while to try to accommodate patients, which is of course asking a lot of hard-pressed doctors, nurses and other professionals, but would certainly help clear the backlog. Those staff deserve thanks for succeeding in keeping so many of the health board's services running smoothly in spite of this mishap.

IT systems are easy to take for granted, but how they work is a complete mystery to most every day computer-users. That lack of understanding can create a sense of helplessness in the face of IT problems. In the run-up to the year 2000, fears that the "millennium bug" could paralyse multiple systems created a collective case of the jitters, as people imagined disaster movie scenarios unfolding on Britain's streets. Those fears turned out to be unfounded, but a major public computer system failure does cause expense and disruption, and depends on highly trained specialists to put right.

Is it right, then, for Scotland's public services to be so dependent on IT? It is unavoidable. So embedded is this technology in everyday life, and such is the expectation that business of all sorts can be transacted digitally, that a reliance on computers and IT professionals is inevitable. In any case, the "good" old days of paper-based communications were less efficient and files more prone to loss or damage.

Information technology has been a boon to public services, but incidents such as NHS GGC's temporary computer failure show that it must never be taken for granted.