A client has been awarded IIDB for a shoulder injury. The percentage was awarded based on a comparison with the schedule for an 'ankylosed shoulder'. One doctor indicated this was 40%, and so awarded the client 18%, while a subsequent doctor used the same comparison but gave a lower figure of 20% and awarded the client 15%. Where would they have found the percentage for the ankylosed shoulder? I've looked in all the obvious places, I think.

You won't find a "percentage figure" for ankylosed shoulder. The only percentages for disablement fixed in legislation are in Schedule 2 to the Social Security (General Benefit) Regulations 1982.

The figures given in the 1982 Regulations are for disablement due to loses of various bits of the body or deafness, loss of sight etc..

The D.W.P.'s "Industrial Accidents and Presribed Diseases and Injuries Medical Assessment Framework" states in the opening paragraph to the section entitled "Assessment of Disablement":
"The assessment of the individual is made by comparing the person with a person of the same age and sex whose physical and mental condition is normal."

"Prescribed degrees of disablement for certain condition are laid down in the Reulations. (The 'Scheduled assessments' or 'Schedules').

"When advising on the assessment of disablement not covered by the Schedules the doctor will endeavour to equate the disablement to the Schedules."

There is nothing in the 1982 Regulations which gives a percentage for an ankolysed shoulder.