Photocopy of article "Psychometric Properties of the Neck Disability Index" co-authored by Judith Waalen, Francois Hains, and Silvano Mior. Published in the February 1998 edition of the Journal of Manipulative and Physiological Therapeutics.

Photocopy of article "Response Set Bias, Internal Consistency and Construct Validity of the Oswestry Low Back Pain Disability Questionnaire" co-authored by Judith Waalen, Anthony C. Tibbles, and Francois Hains.