Table 1 Variables for data analysis

The OCI database

Primary affected joints

Hip = 1

Knee = 0^a

Information was in the Orthopedic Central Intake Patient Referral form.

Diagnosis

Osteoarthritis = 1

Others = 0^a

Information was in the Orthopedic Central Intake Patient Referral form.

Age

< 65 = 1

≥ 65 = 0^a

We chose the age threshold at 65 for two reasons. First, from a methodological viewpoint, one of the most practical ways of defining a senior is the age marker of 65. Second, from a conceptual viewpoint, defining the individuals aged 65 receive full pension benefits in Canada [47].

Patient’s preference

Next available = 1 Specific surgeon = 0^a

The SEM provides patients with two choices: the ‘next available surgeon’ and ‘a specific surgeon’ on the Orthopedic Central Intake Patient Referral form.

The date on the referral form

WT1 starts when a family doctor refers a patient to the OCI clinic. To measure the starting point of WT1, the referral date to the OCI clinic was used.

The date of the first consultation

The date of the first consultation with an orthopedic surgeon was used to measure an ending point of WT1.

Initial referral form

Incomplete = 1

Complete = 0^a

Incomplete referral form status was indicated by incomplete clerical dates. Based on this information, it is possible to know whether a referral form was or was not completed

Priority

P1 = 1

P2 = 2

P4 = 3

P3 = 0^a

In the Eastern Health region, the routine priority classification has four categories: priority 1 – the highest priority; priority 2 – moderate priority; priority 3 – low priority; and priority 4 – probably unsuitable for surgery

Year of referral

2011–2013 = 1

2014–2016 = 2

2017–2019 = 0^a

The year when patients were referred by family doctors, as indicated

in the Orthopedic Central Intake Patient Referral form

The TJAC database

Date of a decision to treat

WT2 begins on the date when a surgeon and a patient decide to have surgery.

Date of surgery

The date of surgery was used to measure the endpoint of WT2.