Catwalk sample size items are rarely understood outside the world of fashion. Partly because they are an average two to four in British sizing and not many of us would be able to squeeze into them.

Fitted directly on to models who are chosen by the designers or casting scouts, they are generally slimmer — and younger — than those featured in glossy fashion magazines.

This is partly because designers believe that slimmer frames show off their clothes in a better light and make a bigger impact when the catwalk images are reproduced.

Another reason is that less established designers are also limited to the models they can use.

Without the production budgets of the big labels they are restricted to less experienced girls or what is known in the industry as “new faces”. These younger girls, often in their early teens, are not physically fully developed.

While brands such as Dior, Prada and Armani can afford to make several different sample collections, up-and-coming designers can produce only one — which is shown on the catwalk.

And this is where sizing issues occur. Unlike newspapers, which work to short lead times and can shoot clothes in larger sizes from the boutiques, magazines shoot with a three or four-month lead time and are restricted to using the catwalk samples as the designs have yet to go into production.

Magazines also have to dress celebrities who may be a healthy size ten but are nothing like the “size ten” samples the designers send in.

It is also frustrating for fashion publications as they have a responsibility to uphold to their readers. Not only must they be careful to use models with attainable bodies but they need “to sell” what the model is wearing. This is why some magazines alter the finished images to make the models look a little fuller in the figure.

With the current trend for reinventing supermodels or using older models, designers may well have to rethink how they go about sizing their collections.

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