We read the paper by Soysal et al. (Reference Soysal, Usarel, Ispirli and Isik2017) with interest as we have experience of both the Attended With (AW) and the Head-Turning Sign (HTS) in a neurology-led cognitive disorders clinic.

In our studies, we focused on the “Attended Alone” (AA) sign as a marker of cognitive health, rather than AW as a marker of cognitive impairment. Re-examining our data (Larner, Reference Larner2014), we present (Table 1) our findings for AW, rather than AA, for ease of comparison with the findings of Soysal et al. (Reference Soysal, Usarel, Ispirli and Isik2017).

Table 1. Measures of discrimination with 95% CI for AW and HTS for any cognitive impairment (dementia and MCI) versus no cognitive impairment

Hence, AW is a high frequency sign (66.1% of all clinic attenders in our study; 69.7% in Soysal et al. (Reference Soysal, Usarel, Ispirli and Isik2017)) which is sensitive but not specific for cognitive impairment (hence, high false positive rate but low false negative rate) with low positive predictive value.

Our studies of HTS (see Larner, Reference Larner2018 for details) encompass two patient cohorts (n = 398 in total, of whom 246 AW) for whom the combined results are shown in the table.

In contrast to AW, we find HTS to be a lower frequency sign (43.1% of all those AW in our studies). In our clinic, we found that HTS is not sensitive but very specific for cognitive impairment (hence, low false positive rate but high false negative rate) with high positive predictive value (Table 1). These findings are consistent across our two patient cohorts, but contrast with the findings of Soysal et al. (Reference Soysal, Usarel, Ispirli and Isik2017), who found HTS to have high sensitivity and negative predictive value for cognitive impairment. The reasons for this discrepancy are not immediately apparent to us, but may possibly relate to methodological factors (HTS may be defined differently in different studies Tabuas-Pereira et al. (Reference Tabuas-Pereira2016)) or cultural factors (HTS had a higher frequency in the Soysal et al. cohort, 244/369 = 66.1% of AW).

Both AW and HTS have the potential advantage of being both easily observed and producing categorical data that is dichotomous. We believe that the diagnostic value of these non-canonical signs merits further examination.