THE decision to call a public inquiry into two scandal-hit hospitals this week has been hailed as a breakthrough that will lay bare what went wrong, who's to blame and the lessons we must learn to prevent such fiascos in future.

Sounds good - but will it?

Across the UK, the number of public inquiries running at any one time has been hovering at around seven to 11 since 2015 - three times the number in the mid-1990s - with a total of 69 taking place between 1990 and 2017.

There were only 19 in total between 1960 and 1990.

If we were learning anything, surely the number of public inquiries would have been falling steadily over time.

READ MORE: Expert says public inquiries tend to deliver same findings 'over and over' 

All too often it seems like demands for public inquiries amount to little more than point-scoring for opposition parties.

Other times it is the knee-jerk response of a Government desperate to take the heat out of a difficult situation and buy some time - quite literally in fact, since the average cost of public inquiries has been £9 million.

For those directly affected by events - especially in NHS inquiries where lives have been lost - the only result they want is the truth, and for those responsible to be held to account.

Whether they get what they wish for is a moot point.

The Penrose Inquiry into the use of infected blood products in Scotland took six years, cost £12m, but was in the end branded a "whitewash" by bereaved families and survivors after it made one recommendation and concluded that there was no evidence that clinicians knew they were making patients ill, nor that the tragedy could have been avoided.

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Inquiries can give answers, but it's not always the answers that people want.

The inquiry into Harold Shipman did lead to tighter regulation of health professionals, but other problems persist - especially around whistleblowing.

The first NHS public inquiry in 1967, into abuse and ill-treatment of patients at Ely psychiatric hospital in Cardiff, concluded that it was "immensely important to have a system whereby such people as nurses can make a case without fear of victimisation".

Yet a 2001 inquiry into the deaths of 29 babies who had had heart surgery at Bristol Royal Infirmary found that whistleblowers had been sidelined and victimised, and the 2013 inquiry into appalling care standards at Mid-Staffordshire Hospital Trust ushered in extra protection for whistleblowers after finding staff who had tried to speak up endured threats, bullying and intimidation.

But time and again, staff across the NHS - including in Scotland – still tell how their careers are ruined by daring to whistleblow.

The latest inquiry cannot be another talking shop that changes nothing.