He seems to have started off with Royal Scots then he is with North Staffordshire Reg. Is the common?
Just to ensure you don't get into trouble with your Scottish relatives who may at this moment be gathering outside your front door with claymores and skean dhu at the ready, it is worth reiterating what Jim said earlier, your man didn't serve with the Royal Scots but with the Royal Scots Fusiliers and yes, in the context of his health issues, being transferred to another regiment was entirely normal.
His medical record shows a number of health issues including a spur on a bone with which he was sent back to England in 1914 the first time, a gunshot wound to the neck with which he was treated and went back to his unit, a diagnosis of debility (weakness/exhaustion) for which he was again sent back to UK in 1915 and finally a diagnosis of jaundice for which he was sent home for the third time in 1918. They certainly got their moneys worth from your man!
The medal card you posted shows his entitlement to the 1914 Star, the British War and Victory Medals for his service. They would have been sent to him in the early 1920s.
There are war diaries which will show where his units were when he was with them in France. These almost never mention individual soldiers. Let us know if that additional info will be of use.
MaxD