It is wrong to say there was no National Registration in 1915 (not 1914) as there was in fact one taken.
It was very much like the 1939 National Registration in its scope and was taken on 15th August 1915, the enumeration forms were collected and collated at local level and the statistical information passed on to the Director General.
The completed forms were kept at a local level until 1921 when it was ordered that they be destroyed.
However Gloucestershire Archives have discovered 2409 returns that were not destroyed relating to women in Cirencester and these have been transcribed and are available using this link (note it is an automatic download)
http://www.rootschat.com/links/01pl3/For more details see
http://www.rootschat.com/links/01pl2/Cheers
Guy
P.S. It is very possible that other archives may have similar returns uncatalogued sitting in piles in basements and attics etc. as most archives have many piles of uncatalogued records, never give up hope.