The aim of this cluster randomized controlled trial is to improve the number of effectively referred patients with IRD to the rheumatology outpatient clinic with either use of validated referral pro formas or triage of IRD by specialists in a primary care setting compared to usual care. In addition, the investigators want to provide tools for the general practitioner to recognise IRD and improve early referral of patients with IRD, and a cost-effectiveness analysis will be performed to evaluate the decreasing effect on health-care cost.

Rationale: Currently, only 22% of all patients referred to the rheumatologist by primary care are diagnosed with an inflammatory rheumatic disease (IRD). Previous research has shown that structured referral sheets and community-based specialist service improve appropriateness of referrals.

Objective: The aim of this study is to improve the number of effectively referred patients with IRD to the rheumatology outpatient clinic with either use of validated referral pro formas or triage of IRD by specialists in a primary care setting compared to usual care. In addition, the investigators want to provide tools for the general practitioner to recognise IRD and improve early referral of patients with IRD, and a cost-effectiveness analysis will be performed to evaluate the decreasing effect on health-care cost.

Study design: Cluster randomized trial with randomization of general practitioner clinics.

Study population: Primary care patients of 18 years or older who are suspected of an IRD and considered by a GP for referral to a rheumatologist.

Intervention: One group of GPs will use a standardized referral strategy for IRD, another group will consist of triage by a rheumatologist in the local primary care clinic, the third group is usual care.

Main study parameters/endpoints: Percentage of patients diagnosed with an IRD by a rheumatologists after 12 months. In addition, cost effectiveness, quality of life, work participation and health care costs at baseline and after 12 months.

Nature and extent of the burden and risks associated with participation, benefit and group relatedness: There is no additional risk to participating patients. Patients might benefit from early referral since the referral pro formas point out important aspects of IRD that are frequently overlooked. Patients will be requested to fill in three online questionnaires related to quality of life, work participation and socio-economic costs. There are no additional visits, physical examinations or other tests.

Inclusion Criteria:

• A primary care patient who is referred by the GP to the rheumatology outpatient clinic
• Subject must be able to understand and communicate with the rheumatologist
• Participant must give a written signed and dated informed consent before enrolment.

Exclusion Criteria:

• Limited understanding of the Dutch language.
• Legally incapable or vulnerable subject as described in the Medical Research with Human Subjects Act (WMO).