Objective: This study aimed to assess the relative frequency of clinical features of giant cell arteritis (GCA) and to investigate the predictors of temporal artery biopsy (TAB) outcomes.

Methods: A literature search of Pubmed/Medline, Embase, ScienceDirect, Scopus, Web of Science (WoS), and Directory of Open Access journals (DOAJ) was conducted from January 1, 1990 to February 2025. Observational studies that reported original data on clinical features in patients diagnosed with GCA in accordance with 1990 ACR and/or 2022 ACR/EULAR classification criteria were deemed for inclusion. A random-effects meta-analysis was performed to determine the pooled prevalence estimates. The study's design adhered closely to the MOOSE standards. The JBI appraisal tool was used to evaluate the risk of bias. The study's protocol was pre-registered on PROSPERO (ID: CRD42024584763).

Results: Out of initial 12,628 records, 62 articles (9971 patients) met all of the eligibility criteria. Mean patients' age upon diagnosis was 74.33 years (95%CI: 74.12-74.54 years). The most prevalent clinical feature of GCA was new-onset headache (75.7%; 95CI%: 72.2-79.0; 95%PI: 0.47-0.92). Other common symptoms of GCA were temporal artery abnormalities (51.5%; 95%CI: 45.2-57.7; 95%PI: 0.25-0.77), weakness/malaise (46.7%; 95%CI: 35.4-58.4; 95%PI: 0.09-0.88), and scalp tenderness (39.1; 95%CI: 35.3-43.1; 95%PI: 0.22-0.59). Positive TAB results were present in 73.8% of patients (95%CI: 68.1-78.8%; 95%PI: 0.35-0.94). The presence of headache (LogOR = -1.11; 95%CI: -1.92 to -0.29) or PMR (-0.71; 95%CI: -1.09 to -0.32) significantly decreases the chance of receiving positive TAB results.

Conclusions: Since there is a greater likelihood of obtaining negative biopsy results, the TAB may not be required when a patient exhibits a headache along with other clinical symptoms that enable them to be diagnosed with GCA.