Our evidence hierarchy

Not all evidence proves the same thing. We rank sources roughly like this, and say on each page what a source can and cannot show.

  1. Dated objects — tools, hairpieces, product packaging, patents and salon equipment.
  2. Primary visual sources — portraits, photographs, film and advertisements, read for staging and bias.
  3. Written primary sources — manuals, trade journals, diaries, letters, catalogues, price lists, school and workplace rules.
  4. Peer-reviewed scholarship — in hair, fashion, gender, race, labour, childhood and material culture.
  5. Museum and archive interpretation, and official legal or health guidance.
  6. Reputable journalism — for how things were received at the time.
  7. Social media — only as a captured, attributed primary source, never as proof of how widespread something was.

Reading images critically

A studio portrait proves a chosen presentation at one moment, not daily practice. For every image we record:

  • creator, date and how precise that date is
  • place, and who the subject is (if known)
  • purpose, audience, staging and retouching
  • the history of its caption
  • how much of the hair is visible, and any headwear
  • source, identifier and rights
  • what the image cannot establish

Read the guide to dating hair in family photographs.

Source guides

Bibliography

Archives and collections to search

These are research leads, not endorsements, and none of them has checked this site. Always search the catalogue itself.