2011. Vol.2, No.3, 210-215
Copyright © 2011 SciRes. DOI:10.4236/psych.2011.23032
Psychometric Properties of a Persian-Language
Version of the Obsessive-Compulsive Inventory-Revised:
Habibollah Ghassemzadeh1*, Giti Shams1, Jamal Abedi2, Narges Karamghadiri1,
Narges Ebrahimkhani1, Mansoureh Rajabloo3
1Roozbeh Hospital, Department of Psychiatry Tehran University of Medical Sciences, Tehran, Iran;
2School of Education, University of California, Davis, USA;
3Private practice, Tehran, Iran.
Received October 17th, 2010; revised March 4th, 2011; accepted April 5th, 2011.
The psychometric properties of the Persian-language version of Obsessive-Compulsive Inventory-Revised
(OCI-R) were studied in a sample of Iranian college students (N = 450). The total and each of the subscales of
OCI-R-Persian demonstrated very high internal consistency as well as high test-retest reliability. Convergent and
divergent validity of the OCI-R-Persian total scale and subscales were satisfactory. In general, the
OCI-R-Persian appears to be a reliable and valid measure of obsessive-compulsive symptoms in this non-clinical
sample of Iranian college students.
Keywords: Confirmatory Factor Structure, OCD, OCI-R-Persian, Psychometric Properties
The utility of using psychological measures of obsessive-
compulsive disorder (OCD) in both research and clinical set-
tings is widely recognized (Goodman and Price, 1998; St. Clare,
2003). Many of these measures are based on self-report of
symptoms. In a review of different self report measures, Foa,
Kozak and Salkovskis (1998) addressed some of the problems
and limitations inherent in such instruments as Yale-Brown
Obsessive-Compulsive Scale (YBOCS; Goodman et al., 1989),
Layton Obsessional Inventory (LOI; Taylor, 1995), the Com-
pulsive Activity Checklist (CAC; Cottraux et al., 1988), and the
Maudsley Obsessive-Compulsive Inventory (MOCI; Hodgson
& Rachman, 1977). Based on their critical review, Foa and her
colleagues (1998) introduced a new obsessive-compulsive dis-
order scale called the Obsessive-Compulsive Inventory (OCI).
This scale consists of 42 items grouped in seven subscales
(checking, washing, obsessing, mental neutralizing, ordering,
hoarding and harming, and doubting). The subscales are further
divided up into frequency and distress dimensions.
The OCI showed “excellent” internal consistency and “satis-
factory” test-retest reliability for both symptom frequency and
associated distress in individuals with OCD and in non-patient
controls. The coefficient alphas for OCI total score in OCD
group were .93 for frequency and .92 for distress. The same
coefficients were .94 and .95 in control group. The test-retest
reliabilities for OCI total score in OCD group were .84 for fre-
quency and .87 for distress. The same coefficients were .90
and .89 in control group (Foa et al., 1998). These researchers
further introduced a revised shorter version of the OCI, the
OCI-R. Several considerations led to the revision: 1) there was
a high correlation between the distress and frequency total
score (above .90) in the original OCI, indicating redundancy in
the two scales; 2) the time needed for the completion of OCI
made it somewhat difficult to use in the clinical and/or hospital
settings; and 3) the number of items varied across scales in the
original OCI. The OCI-R consists of 18 items, yielding six
subscales: washing, checking, ordering, obsessing, hoarding,
and neutralizing. It is significantly shorter than OCI, and elimi-
nates the frequency scale. Each subscale has three items which
are summed up, facilitating comparisons across scales. The
psychometric properties of the OCI-R were assessed by Foa and
her colleagues (2002). The subsequent studies have provided
further support for the psychometric properties of OCI-R in both
clinical and non-clinical samples (e.g., Hajcak et al., 2004;
Abramowitz & Deacon, 2006; Smari et al., 2007).
OCD Measures in Iran
A number of instruments for assessment of OCD symptoms
have been previously translated into Persian (Farsi) and used in
Persian speaking patient and non-patient populations. In an
earlier study (Ghassemzadeh et al., 2002) we examined the
symptoms in a sample of Iranian OCD patients using Persian
translations of the Maudsley Obsessional-Compulsive Inven-
tory (MOCI) and Compulsive Activity Checklist (CAC). In our
study, the mean scores on MOCI (M = 15.73, SD = 5.63) and
CAC (M = 14.90, SD = 9.77), were close to those reported in
other settings. However, we encountered numerous problems in
using MOCI in this setting. First, some of the items were not
easily understood by the patients, especially the double-nega-
tive sentences (e.g. “I don’t worry unduly about contamination
if I touch an animal.”). Second, the true-false response format
of MOCI made it difficult for many indecisive patients to re-
spond. Third, as Foa et al. (1998) suggested the items of the
MOCI encompass only two of the behavioral compulsions (i.e.
H. GHASSEMZADEH ET AL. 211
checking and washing) and do not measure specific obsessions
other than contamination. These difficulties with MOCI moti-
vated us to translate and examine the feasibility of the OCI-R in
the Iranian culture. In our preliminary work, we found OCI-R
practical and easily understood by most respondents. Having
fewer items than MOCI, using a 5-point Likert scale response
format, and equal number items for every subscale are other
important aspects of OCI-R. In this report, we present the re-
sults of a study of the psychometric properties and construct
validity of the Persian translation of the OCI-R in a sample of
450 Iranian male and female college students.
The sample consisted of 450 (164 males and 286 females)
student volunteers recruited from Tehran University of Medical
Sciences and Allameh Tabatabai University, both in Tehran,
Iran. The average age of the total sample was 22.12 (SD = 3.95)
for males and 22.83 (SD = 3.53) for females.
Obsessive-Compulsive Inventory-Revised (OCI-R)
The OCI-R is an 18-item instrument developed based on the
earlier 42-item version (Foa, Kozak, & Salkovskis et al., 1998;
Foa, Huppert, & Leiberg et al., 2002). The OCI-R comprises
six scales: (1) Washing, (2) Checking/doubting, (3) Obsessing,
(4) Mental neutralizing, (5) Ordering, and (6) Hoarding. Each
item is rated on a five-point (0 - 4) Likert scale for distress or
bother during the past month. The total score ranges from 0 to 72.
The original English version of OCI-R was obtained from Dr.
Edna Foa at the University of Pennsylvania and translated to
Persian by the first author (H. G.). The Persian draft was then
back-translated by a professional bilingual translator. The back
translated version was then sent to one of the colleagues of Dr.
Foa who reviewed the English text and provided suggestions to
improve the accuracy of the Persian translation. After incorpo-
rating those points in the translation and going through to the
process of second back translation, the final version of OCI-R
Persian was ready to use in our sample.
Mausley Obsessional-Compulsive Inventory
The MOCI is a 30-item true-false instrument for assessment
of OCD symptoms. Maximum scores for the five scales (total,
checking, washing, slowness-repetition, and doubt-conscien-
tious) are 30, 9, 11, 7, and 7, respectively. This inventory has
been used with adequate validity and reliability (Rachman &
Hodgson, 1980). The Persian language version of the test has
been used in a number of studies in Iran (Ghassemzadeh, 2002,
Compulsive Activity Checklist (CAC)
The original format of this inventory had 62 items concern-
ing specific daily activities rated on a 4-point scale of severity.
We used a French version of CAC, which is an abbreviated
form of the instrument and contains 19 items centered mainly
on checking behavior and rituals (Cottraux et al., 1988). Each
item is rated on a four-point (0 - 3) scale, therefore the scores
range from 0 to 57. Different versions of CAC have demon-
strated good internal consistency (St. Clare, 2003). This test has
been translated into Persian and used in our previous studies in
Iran (Ghassemzadeh et al., 2002, 2005b).
Beck Depression Inventory-II- Persian Version
BDI-II is the second edition of the widely used 21-item in-
ventory, the BDI. Originally developed in 1960s (Beck et al.,
1961), BDI-II was revised to approximate the DSM-IV criteria
for major depression. Scores on each item range from 0 to 3,
yielding a possible maximum total score of 63. The Persian
version of this test (BDI-II- Persian) is widely used in various
settings in Iran. Its psychometric properties have been exam-
ined elsewhere (Ghassemzadeh, et al., 2005c).
All the tests were administered to the students in a group set-
ting during a class session after a brief description of the pur-
pose of the study. The students were told that the participation
is voluntary and no payment or course credit was offered to the
participants. The OCI-R was administered first, followed by
MOCI, CAC and BDI-II. All the assessments were repeated in
the same sample after 2 weeks. Due to some logistical issues,
MOCI, CAC and BDI-II were administered only to 228 sub-
jects of the total sample.
Descriptive Statistics of the OCI-R Scale and
The means and standard deviations on the OCI-R (total and
subscales) for males and females (separately and total) are pre-
sented in Table 1.
As the data in Table 1 show, female students generally
scored higher than males on most subscales. However, the dif-
ference reached a statistically significant level only on the “ob-
sessing” subscale (t = 2.27, df = 448, P < .05).
Table 2 shows the mean scores obtained in the present study
as compared with Foa’s group (2002). Our mean score for the
whole group is very close to their mean score (18.46 vs. 18.82).
This is true for some subscales but with some considerations.
Since Foa’s group was regarded as non-anxious control and our
group as normal college students, it would be difficult to com-
pare the results of these two studies.
Correlations amon g O CI-R Subscal es
Correlations between each of the subscales and the total scale
of the OCI-R as well as the inter-correlations among the sub-
scales are shown in Table 3. Correlations between each of the
subscales and the total scale ranged from .63 (ordering) to .76
(obsessing). Inter-correlations among the subscales ranged
from .21 (neutralizing & ordering) to .51 (hoarding & obsess-
ing). All the correlations were significant at .01 level.
Test-Retest Reliability and Internal Consistency
The two-week test-retest reliability was calculated using
Pearson’s r correlation coefficients. Cronbach’s alpha was cal-
culated and used to assess the internal consistency of the OCI-R
H. GHASSEMZADEH ET AL.
Scores on the OCI-R scale a mo n g 450 f e m a l e a n d m a l e Iran i a n c ol l e g e s t udents.
(N = 450)
(N = 286)
(N = 164)
(df = 448)
M S.D. M S.D. M S.D.
Checking 2.38 2.26 2.42 2.35 2.32 2.09 .45
Hoarding 3.49 2.49 3.59 2.59 3.30 2.30 1.18
Neutralizing 1.09 1.74 1.11 1.72 1.07 1.79 .24
Ordering 5.16 2.87 5.13 2.96 5.22 2.70 −.33
Washing 2.19 2.21 2.24 2.28 2.11 2.09 .59
Obsessing 4.15 2.90 4.38 3.01 3.74 2.65 2.27*
Total 18.46 9.92 18.86 10.44 17.76 8.93 1.13
*p < .05.
The mean and SD s cores of OCI -R (total and su bscales) in the prese nt study a nd Foa’s me an and SD scor es for non- anxiou s contr ols (NACs).
(N = 477)
(N = 450)
M S.D. M S.D.
Checking 2.91 2.56 2.38 2.26
Hoarding 4.41 2.67 3.49 2.47
Neutralizing 1.82 2.20 1.09 1.74
Ordering 4.40 3.03 5.16 2.87
Washing 2.41 2.50 2.19 2.21
Obsessing 2.86 2.72 4.15 2.90
Total 18.82 11.10 18.46 9.92
Correlations between OCI-R subscales and total scale and inter -correlations among th e su bscales.
OCI-R Checking Hoarding Neutralizing Ordering Washing Obsessing
Checking 1 .47 .26 .31 .48 .49
Hoarding 1 .32 .29 .41 .51
Neutralizing 1 .21 .22 .31
Ordering 1 .36 .29
Washing 1 .42
All p-value < .01.
total scale, as well as the subscales (Table 4). The OCI-R total
scale as well as its subscales demonstrated very high test-retest
correlations and internal consistency.
Convergen t a nd Divergent Val i di ty of the OCI-R
Total Scale and Subscales
Convergent validity of OCI-R total scale was determined by
correlating the OCI-R with two other measures of obsessive-
compulsive symptoms, the MOCI and CAC, which have been
used in the previous studies of OCD in this setting (Ghas-
semzadeh et al., 2002, 2005a). The correlations between the
OCI-R total and subscale scores with MOCI total, washing and
checking subscales are presented in Table 5.
The MOCI and the CAC total scores correlated .571 and .475,
H. GHASSEMZADEH ET AL. 213
respectively with OCI-R, indicating moderate convergent
Correlations of OCI-R checking and washing subscales with
corresponding subscales of MOCI were .558 and .338, respec-
tively. But the highest correlation (.575) was related to MOCI
total score with OCI-R checking subscale. Correlations among
different subscales of OCI-R and MOCI washing and checking
subscales varied from .130 to .575.
The divergent validity of OCI-R was assessed by correlating
the OCI-R total and subscale scores with BDI-II (Table 6). The
correlation between OCI-R total and BDI-II as a distinct meas-
ure from OCD was .398, indicating a lower correlation than the
Factor Structure of OCI-R-Persian
A confirmatory factor analytic model was used to examine
the conceptual structure underlying the OCI-R, the Persian
version. These analyses were conducted using EQS software
(Bentler, 1992). Two SEM models were created. In the first
model all the subscales include 3 items- the same as Foa’s (Foa
et al., 2002) findings except “neutralizing” which includes 2
items (item 16 was excluded) and washing which includes 4
items (item 16 was added to this subscale). Item 16 in the
original Foa’s scale was part of the “neutralizing” subscale.
Test-retest reliability and internal consistency coefficients for OCI-R
total scale and subscales.
OCI-R Test-retest Cronbach’s alpha
Checking .70 .82
Hoarding .73 .84
Neutralizing .62 .77
Ordering .69 .82
Washing .66 .80
Obsessing .76 .86
Total .75 .85
Convergent validity for the OCI-R-Persian subscale and total scores.
(N = 228)
(N = 228)
(N = 450)
Total Washing Checking Total
Checking .575 .314 .558 .359
Hoarding .378 .193 .291 .365
Neutralizing .191 .130 .185 .275
Ordering .223 .184 .137 .111
Washing .394 .338 .333 .412
Obsessing .524 .300 .527 .397
Total .571 .365 .506 .475
Divergent Validity for OCI-R- Persian.
(N = 450)
(N = 228)
Alternatively, the second model included item 16 in the “neu-
tralizing” subscale as was originally suggested by Foa. Table 7
presents the results of SEM analyses for Model 1 and Table 8
reports the results for Model 2. For both models, we have as-
sessed all the fit indices reported in the SEM literature includ-
ing Normed Fit Index (NFI), Comparative Fit Index (CFI),
Joreskog-Sorbom’s GFI and standardized Root Mean-Square
Residuals (SRMR) (Bentler & Bonett, 1980; Bollen, 1989). As
it can be seen from both Tables 7 and 8, these fit indices are all
at the satisfactory level and suggest a good fit of the data to the
models. For model 1 the NFI is .876 and the GFI for this model
is .928 both suggesting a good fit. Similarly, for model 2, the
NFI is .876 and the GFI is .929 almost identical with the fit
indices of Model 1. Other fit indices reported for the two mod-
els are also almost identical suggesting that both models fit
equally to the data: CFI = .919 for both models; SRMR = .049
(model 1) and .054 (model 2); RMSEA = .060 for both models.
It is usually believed that NFI, CFI, and GFI values of .90 or
greater and SRMR and RMSEA values of .10 or less are mark-
ers of an acceptable fit (Hu & Bentler, 1999). These values in
our study are in an acceptable range.
However, examination of the factor structure of the two
models reveals that item 16 does not fit well under any of the
two models. In fact, this item has the lowest loading with its
latent variable (“ordering” or “neutralizing”) than any other
items with their respective latent variables in both models. This
item does not share a common variance with many other items
included in the inventory. Therefore, it does not make much
difference to include it in either “ordering” or “neutralizing”
subscales. There might be some issue with this item, which will
be considered in discussion section.
Considering the fact that our results, in general, support the
original subscales developed by Foa’s group (2002), we ana-
lyzed our data based on a six-factor model.
Overall, the OCI-R appears to have excellent psychometric
properties in this relatively large sample of Iranian college stu-
dents. This finding is consistent with those from a number of
earlier studies examining the psychometric properties of OCI-R
in non-clinical samples from the US (Foa et al., 2002; Hajcak et
al., 2004), Spain (Fullana et al., 2005), and Iceland (Smari et al.,
H. GHASSEMZADEH ET AL.
2007). Our work extends this line of investigation by examin-
ing the psychometric properties of OCI-R in a non-Western
The OCI-R-Persian has excellent internal consistency (alpha
ranges from .77 to .86) and test-retest reliability (correlations
ranges from .62 to .76). The correlations between subscales and
total scale vary between .51 and .76, indicating a large correla-
tion. But inter-correlations between the subscales were only
moderate. The lowest inter-correlations were related to neutral-
izing. The test-retest reliability for total scale was .75. Although
the coefficients were smaller than Foa’s group (2002),
Model 1, with 6 factors, item 16 loading on “ordering”.
Factors (Subscales) Questions Factor Structures
3. Neutralizing Q 4
Model 2, with 6 factors, item 16 loading on “neutralizing”.
Factors (Subscales) Questions Factor Structures
3. Neutralizing Q 4
all of them indicated excellent test-retest reliability. Our test-
retest reliabilities were in general somewhat higher than the
scores reported in Hajcak’s et al. (2004). For example, their
obtained value for total scale was .70, which was lower than
our value (.75). But their reported values for washing, checking
and obsessing were somewhat higher than our values. Fullana’s
et al. (2005) obtained a test-retest reliability of .67 which is
lower than our value. Their obtained scores for the subscales
were also smaller than our scores.
Similar to other studies (e.g. Fullana, et al., 2005), we found
that OCI-R correlated strongly with other measures of OCD
symptoms (such as MOCI and CAC). Satisfactory convergent
validity is indicated by positive correlation of OCI-R-Persian
total score with the total scores of MOCI and CAC (.571
and .475, respectively). Furthermore, the checking subscale of
the OCI-R-Persian and MOCI was also positively correlated (r
= .558), but the correlation between two washing subscales of
OCI-R-Persian and MOCI was not very high (r = .338). This
may be partly related to the emphasis on obsessionality in
comparison to compulsivity in OCI-R as compared to MOCI.
Another reason may be related to the differences between the
formats of two tests. The OCI-R is scored on a Lickert-scale
whereas the MOCI is scored with a true-false format.
Apart from the problem of item 16, neutralizing subscale it-
self is somewhat questionable in the original version of OCI-R.
The Cronbach’s alpha for this subscale was .34 (the lowest),
while the coefficients for the total scale and other subscales
were all high, ranging from .65 to .89 in Foa et al. study (2002).
Although in our study Cronbach's alpha for neutralizing was
good (r = .77), it was lowest as compared to other subscales.
We found the same trend in test-retest reliability (Table 4). The
correlation between this subscale with the total scale in our
study was .51, while the correlations for other subscales with
the total scale ranged from .63 to .76. As Abramowitz and
Deacon (2006) have indicated the findings suggest that the
neutralizing subscale is misnamed and possesses weaker con-
struct validity than other OCI-R subscales. It may measure
completely different construct than other items or the wording
(linguistic structure) of the item is complex creating some dif-
ficulties in comprehending this item, or there might be some
unique cultural aspect to this item that may not provide the
same meaning across different subgroups. Therefore, this item
can be considered as “attention” item that needs a careful re-
view and inspection.
We found that female students had somewhat higher OCI-R-
Persian total and subscales scores than males but this did not
reach statistical significance, except in the case of obsessing (t
= 2.27, df = 448, P < .05). No systematic evaluation of sex
differences were provided in the past OCI-R research (Fullana
et al., 2005). In our earlier studies with OCD patients in Iran,
we found significant differences between females and males (F
> M) in the total mean scores as well as in washing subscale of
MOCI. The same trend was found in CAC, but not in Y-BOCS
total or subscale scores (Ghassemzadeh et al., 2002, 2005b).
In conclusion, we found the OCI-R-Persian to be a brief and
time-efficient measure of obsessions and compulsions in the
general population in this setting. Participants had no difficulty
in understanding the questions. Thus, it is an ideal measure for
use for screening and epidemiological research in large general
H. GHASSEMZADEH ET AL. 215
Future work needs to examine the psychometric properties of
OCI-R-Persian in clinical samples and its utility as a measure of
change of OCD symptomatology in clinical setting (c.f.
Abramowitz & Deacon, 2006). Future work also needs to as-
sess the potential utility of OCI-R in distinguishing OCD from
other types of anxiety disorders and depression in this setting.
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