The objective of this study is to evaluate the effect of adalimumab on health outcomes in participants with rheumatoid arthritis, ankylosing spondylitis and plaque psoriasis.

Inclusion Criteria:

• Participants with a diagnosis of rheumatoid arthritis, ankylosing spondylitis or plaque psoriasis
• Decision to initiate Humira® treatment in accordance with routine medical practice and in compliance with eligibility for adalimumab based on the local label
• Prior to any study-specific procedures, participant has voluntarily signed the authorization (or informed consent where applicable) to disclose and use anonymized personal health information after participate in this research.

Exclusion Criteria:

• Inadequate response to previous standard treatment with anti-tumor necrosis factor (TNF) biological agent according to the physician's clinical judgment.
• Participant has been treated with adalimumab within 70 days (five half-lives) prior to the Baseline Visit.
• Participants discontinued due to adverse drug reaction of previous adalimumab treatment.
• Participants who fulfill any of the contraindications as per adalimumab label in China.
• Participants, who in the clinician's view, may not be able to comply with the study requirements.

Chinese participants diagnosed with rheumatoid arthritis, ankylosing spondylitis or plaque psoriasis, for whom adalimumab (Humira®) treatment has already been decided as per local label, will be recruited from within the clinical setting of each rheumatologist or dermatologist participating in the study.