Table 1.
Selection criteria
| Author | Study design | Endocrinological diagnosis of thyroid status | Ophthalmological diagnosis of TED | Exclusion of secondary to thyroid disease treatment thyroid hormone status at TED onset | Observations |
|---|---|---|---|---|---|
| Ackuaku-Dogbe et al. [24] | Cross-sectional | Thyroid function tests and physical examination | By ophthalmologist | Authors measured the thyroid status at the time the first treatment of the disease was established | NA |
| Expósito et al. [25] | Cross-sectional | Thyroid function tests | According to information register in clinical records | Information of basal hormonal status was extracted from the data of the cause of the disease (GD or Hashimoto thyroiditis) | This study only includes glucocorticoid-treated patients for an active moderate-severe TED status and does not explain through which criteria the patients were diagnosed with TED |
| Bartley et al. [14] | Cross-sectional | Thyroid function tests | By ophthalmologist and imaging tests | Authors measured the thyroid status diagnosis index registered on the medical records | The patients classified as primary hypothyroidism and Hashimoto thyroiditis (all patients were in hypothyroid status) were merged into the hypothyroid group to calculate the prevalence |
| Eckstein et al. [15] | Cohort study | Thyroid function tests | According to information register in clinical records | Investigators measured the thyroid status before or within 6 months after the onset of TED | NA |
| Jang et al. [26] | Case-Control | Thyroid function tests | By ophthalmologist and CT scans | The diagnosis of euthyroidism was based on normal serum hormone levels and no clinical history of hyperthyroidism. Hyperthyroidism was established using hormonal criteria and if the patient had a history of antithyroid therapy, in this last group only patients that remained hyperthyroid were included. | Hypothyroid patients were not included in the study |
| Kashkouli et al. [23] | Cross-sectional | Thyroid function tests, thyroid gland-scan, and sonography | By a specialized ophthalmological clinic | The classification of thyroid hormone status was made according to the primary thyroid diagnosis register on the clinical records | A limitation of this study is the underestimation of euthyroid patients. This study included patients from the thyroid disorder and not from the ophthalmological diagnosis, euthyroid patients were excluded from the beginning and therefore were not evaluated by ophthalmology |
| Khoo et al. [27] | Cohort study | Thyroid function tests | By experienced endocrinologists and for equivocal cases further evaluations were carried out by ophthalmology colleagues | The study did not mention possible causes of secondary hormonal status on the patients (following thyroid disease treatment) | The total number of patients with TED identified at the Thyroid Clinic was calculated according to the patients that were initially included in the study (1020). 1001 were excluded because they had previous history of thyrotoxicosis or hyperthyroidism (we included these patients into the hyperthyroid group), 10 had subclinical thyrotoxicosis (these patients were added to the hyperthyroid group), and the other 9 patients were in hypothyroid or euthyroid status |
| McKeag et al. [28] | Cross-sectional | Thyroid function tests | By ophthalmologist and imaging tests | The criteria of the study included only patients with Graves’ thyrotoxicosis before or at the time of diagnosis of TED and only patients with primary hypothyroidism are named in the study. | |
| Medghalchi et al. [29] | Cross-sectional | Thyroid function tests | By ophthalmologist, imaging tests and visual field analysis | The study did not mention possible causes of secondary hormonal status on the patients (following thyroid disease treatment) | |
| Mukasa et al. [30] | Cross-sectional | Thyroid function tests | By a specialized ophthalmological clinic | All the patients included were untreated and were assessed for GO within 3 months of their initial visit to the hospital | It is not clear if the prevalence of hypothyroidism was cero in this group or if at the beginning of the study these patients were excluded |
| Ponto et al. [31] | Cross-sectional | By a specialized autoimmune (endocrine) clinic | By independent ophthalmologist or a specialized thyroid–eye clinic | The primary hormone levels were measured according to the autoimmune-associated thyroid disease | A limitation of this study is the underestimation of euthyroid patients. This study initially included patients with autoimmune thyroid disease (GD and Hashimoto’s thyroiditis), euthyroid patients were not included in the initial selection criteria and were gathered with hypothyroid patients |
| Ponto et al. [32] | Cross-sectional | Thyroid function tests | By an ophthalmologist | The primary thyroid status was measured 6 months before or after TED diagnosis | NA |
| Cozma et al. [33] | Cross-sectional | By a specialized thyroid–eye clinic, thyroid function tests | By a specialized thyroid-eye clinic | Patients with normal thyroid function tests, no history of disease or treatment, no clinical signs or symptoms of thyroid disease were included | NA |