I regret I can't offer numerical data but perhaps these observations may be appropriate

1. Since you don't state the reason for dwelling on the 'IOSH WORKING SAFELY' brand name, may I infer that what you are looking for is standardised training of a reliable standard.

2. If my inference is correct, and your inclusion of the expression 'ouch!' suggests that the budget available to you is modest rather than enormously generous, may I suggest that your most cost-effective approach to achieving the objective postulated in (1) above may be to commission a qualifed safety ergonomist ie. CMIOSH and MIEFH (Or MHFES) to assist you to design, illustrate and produce your own e-learning programme, possibly with the additional assistance of a learning technologist?

We don't require contractors have it but they must be able to demonstrate thet their employees have some level of formal safety training.

As a site we have put all our employees and agency workers through either working or managing safely. This is done in house.

We have to put EVERYONE through the CCNSG safety passport to get our staff on sites.

Some of our men have CSC cards but some clients have stated that they aren't good enough so we have to put them ALL through it. At about 180 for 2 days.

Depends on what industry you are in I suppose. We work with high voltage electricity so our clients are very stringent about these things.

Humbug. Bumkum. Institutional Scam. etc.
Look at the depth and complexity of the recommended syllabus within the HSE guidance:

http://www.hse.gov.uk/pubns/indg381.pdf

Any suggestion that those exposed to that amount of information over a 1-day event have been "trained" in any shape of form is simply ludicrous (IMHO of course).

At least HSE have the good grace to add the following riders within INDG318:
Passports are not:
● a way of knowing or identifying that a worker is competent
●a substitute for risk assessment
a way of showing ‘approval’ of a contractor
● required or regulated by law
●a reason to ignore giving site-specific information; or
●a substitute for effective on-site management.

It's certainly a money spinner. Does it add value and improve health and safety compliance? I think not. The HSE's own commissioned Research Report said as much. End of rant (at least for now).