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S28 F. Mammadova et al. / European Psychiatry 27 (2012) / supplement n°2 / S27-S31<br />
2. Materials and Methods<br />
2.1. Translation and pilot studies<br />
The original ZSDS was translated from English into Azerbaijani<br />
and Russian. The translations were then back- translated into<br />
English. The latter were conducted by an independent translator,<br />
who was not familiar with the English original. The back-<br />
translations were compared with the English ZSDS original by a<br />
native English speaker, and were ratifi ed as accurate and valid.<br />
Two pilot studies were conducted to facilitate adaptation<br />
<strong>of</strong> the validated ZSDS translations. The participants were asked<br />
to provide comments as necessary. The first pilot study <strong>of</strong><br />
Azerbaijani and Russian ZSDS versions was conducted among a<br />
sample <strong>of</strong> 30 subjects (21 Azerbaijani- speaking and 9 Russian-<br />
speaking). The fi rst pilot showed high drop- out rate, due to skipping<br />
<strong>of</strong> two items within the scale. These items were reworded<br />
in Azerbaijani and Russian to improve their acceptability. The<br />
reworded items were back translated into English to check<br />
similarity in terms <strong>of</strong> the meaning between the reworded items<br />
and the items in the English original. After the rewording the<br />
second pilot study was conducted among a sample <strong>of</strong> 45 subjects<br />
(42 Azerbaijani- speaking and 3 Russian- speaking) to check again<br />
the acceptability <strong>of</strong> the scale.<br />
The reworded Azerbaijani and Russian ZSDS versions were<br />
chosen <strong>for</strong> further use in the study.<br />
2.2. Reliability study<br />
The second phase <strong>of</strong> the study was a reliability study <strong>of</strong> the<br />
ZSDS Azerbaijani and Russian versions and was conducted on<br />
a sample <strong>of</strong> 175 subjects with a mean age <strong>of</strong> 32.66 SD=11.28<br />
(range 19- 64), 58 males (33.14%) and 117 females (66.86%). 104<br />
(59.43%) subjects <strong>of</strong> the sample were Azerbaijani- speaking and<br />
71 (40.57%) were Russian- speaking. The total sample consisted<br />
<strong>of</strong> 2 sub- samples: depressed patients diagnosed with depression<br />
according to ICD- 10 criteria [20] (n=55) and healthy control<br />
sample (n=120). The depressed patients’ sample (15 males and<br />
40 females) had a mean age <strong>of</strong> 32.74, SD=9.23 (range 18- 61). The<br />
healthy controls sample (43 males and 77 females) had a mean<br />
age <strong>of</strong> 32.61, SD=9.23 (range 19- 64).<br />
The depressed patients were attending Baku the city Psycho-<br />
Neurological Dispensary, outpatient department <strong>of</strong> the Republic<br />
Psychiatric Hospital, “Saglam Aile” Private Medical Center and<br />
“Funda” Private Medical Center, Baku, Azerbaijan. The healthy<br />
control sample was composed <strong>of</strong> members <strong>of</strong> the mentioned<br />
medical centers staff, relatives <strong>of</strong> the patients and the research team<br />
members. All sample subjects were tested once by the Azerbaijani<br />
or Russian ZSDS versions, according the fi rst language they spoke.<br />
All the obtained data were summarized in a database built<br />
on SPSS 16.0 s<strong>of</strong>tware <strong>for</strong> Windows, which was used <strong>for</strong> the<br />
later statistical analysis. Chronbach’s alpha coeffi cient <strong>for</strong><br />
the total scale was calculated to check the reliability <strong>of</strong> the<br />
ZSDS scale adaptations. Item- test correlations and alpha if<br />
item deleted were calculated to check per<strong>for</strong>mance <strong>of</strong> the<br />
individual items. Sensitivity and specifi city <strong>of</strong> the ZSDS scale<br />
at various cut- <strong>of</strong>f levels <strong>for</strong> the total sample were calculated<br />
to choose an optimal cut- <strong>of</strong>f point.<br />
3. Results<br />
The fi rst pilot study revealed a very high drop- out rate <strong>of</strong><br />
25 subjects (83.3%) due to skipping <strong>of</strong> the item 5 (missed out<br />
by 8 subjects (26.7%) and item 6 (missed out by 23 subjects<br />
(76.7%). The participants, who missed items <strong>of</strong> the ZSDS scale,<br />
were interviewed to provide reasoning <strong>for</strong> not completing the<br />
scale. According to comments and explanations, made by the<br />
participants, item 5 (I eat as much as I used to) was missed<br />
out due to the diffi culty in comprehension <strong>of</strong> the item’s word<strong>for</strong>-<br />
word translation. Skipping <strong>of</strong> item 6 (I still enjoy sex) was<br />
explained by the fact that it is culturally unacceptable to report<br />
about one’s sexual activity (or to be sexually active), particularly<br />
<strong>for</strong> local unmarried women (19 out 21 unmarried female participants<br />
(90.0%) missed item 6). There was a high overlap between<br />
subjects not responding both to items 5 and 6, respectively: 6 out<br />
8 subjects (75%), who missed item 5, missed item 6 as well. Such<br />
a high overlap can be explained by a high non- responsiveness<br />
to item 6, which covers 76.7% <strong>of</strong> the total sample in the fi rst<br />
pilot study.<br />
Item 5 was reworded and translated (in back translation) as<br />
“my appetite is as it used to be”. Item 6 was reworded as well,<br />
and translated back into English as “my sexual drive (interest)<br />
is as it used to be”.<br />
In comparison with the fi rst pilot, the second pilot study<br />
<strong>of</strong> the Azerbaijani and Russian ZSDS versions, which was<br />
conducted after the rewording <strong>of</strong> the scale items, revealed a<br />
signifi cantly lower drop- out rate <strong>of</strong> 20.0% (9 subjects) due to<br />
miss <strong>of</strong> item 6. Only 5 out 29 unmarried female participants<br />
(17.2%) missed item 6. There was no miss <strong>of</strong> item 5, as there<br />
had been in the fi rst pilot.<br />
The processing <strong>of</strong> the data from the second phase <strong>of</strong> the study<br />
(reliability study) revealed the following fi ndings: Chronbach’s<br />
alpha <strong>for</strong> the total scale was equal to 0.8727, and this value<br />
suggests that the scale has a good general internal consistency.<br />
However, items <strong>of</strong> the scale did not per<strong>for</strong>m similarly, in terms<br />
<strong>of</strong> the item- test correlations. The range <strong>of</strong> item- test correlations<br />
is signifi cantly wide with the highest correlation <strong>for</strong> item 1 (0.71)<br />
and the lowest <strong>for</strong> item 8 (0.24). Sixteen items, if deleted, would<br />
decrease the total scale alpha. three items (item 5, item 7, and<br />
item 8), if deleted, would increase the total scale alpha, and these<br />
three times have low item- test correlations, which are 0.38, 0.29,<br />
and 0.24 respectively. Item 6, if deleted, would have no impact<br />
on the total scale alpha (Table 1).<br />
Sensitivity and specifi city <strong>of</strong> the scale at various cut- <strong>of</strong>f levels<br />
<strong>for</strong> the total sample were calculated. (Table 2) The results established<br />
that an optimal cut- <strong>of</strong>f point can be suggested at >=45<br />
with sensitivity=90.91%, specifi city=80.83%. The area under ROC<br />
curve <strong>for</strong> ZSDS scores=0.9440. (Fig. 1)<br />
<strong>Pro<strong>of</strong>s</strong><br />
4. Discussion<br />
Publications on using <strong>of</strong> the ZSDS in various cultural contexts<br />
indicate that, despite being successful, there are diffi culties presenting<br />
the language adaptation <strong>of</strong> the scale. Adaptation <strong>of</strong> the<br />
ZSDS <strong>for</strong> using in a Spanish- speaking population demonstrated the<br />
scale’s usefulness [4], but presented interpretation diffi culties <strong>of</strong><br />
the scale’s Spanish version. The spanish version was needed to be