Table 3 Background characteristics and data collection from the other design studies
Reference | Region | Time frame of study | Design of study | Gender | Age, years (average, mean with standard deviation or range) | Cancer outcome with subsite | Case definition | No of Cases | Sample population | Frequency of dental visits | Quality assessment |
|---|---|---|---|---|---|---|---|---|---|---|---|
Bertl et al. [31] | Austria | 2013 | Cross-sectional | M + F | > 18 | HNCs (oral cavity, nasopharynx, oropharynx, hypopharynx, or larynx) | Patients from outpatient cancer clinics | 48 | Tertiary hospital | < 12 months or ≥ 12 months | Moderate |
Langevin et al. [4] | Greater-Boston | 2006–2011 | Case-series | M + F | ≥ 18 | OCs (tongue, salivary gland, gum, mouth), oropharynx and hypopharynx | Incident cases | 441 | Teaching hospital | At least annual, infrequent, rare or never | Strong |
Frydrych et al.[53] | Western Australia | 2005–2009 | Retrospective observational study of medical records | M + F | Average age for M = 59 and for F = 60 | OCs (lip, tongue, gum, mouth, palate) tonsil and oropharynx | Incident cases | 127 | Teaching hospital | Time (months) since the patient’s last dental visit and regularity of attending dental appointments | Moderate |
Watson et al. [1] | Florida | NG | Cross-sectional | M + F | 60 (13.2) | OCs (lip, oral cavity) or oropharynx | Incident cases | 131 | Two tertiary care centres | Within preceding 12Â months, more than 12Â months ago | Moderate |
Lockhart et al. [38] | United States | NG | Screening | M + F | 17–86 | HNCs (not defined) | NG | 131 | HNC clinic | Emergency dental care, annually, regularly or twice yearly | Weak |
Gellrich et al. [32] | Europe | NG | Retrospective observational study of medical records | M + F | Average age of M = 58.2, F = 62.6 | OCs (floor of the mouth, tongue, gingiva, non-specified sites for oral cancer, excluding lip) | Incident cases | 1543 | Oral and maxillofacial surgery departments | Quarterly, annually, twice a year, every 2Â years, less than every 2Â years | Weak |