ABIEBR :: 17.13 Hospital Anxiety and Depression Scale (HADS)

17.13 Hospital Anxiety and Depression Scale (HADS)

The Hospital Anxiety and Depression Scale (HADS), a self-assessment scale, was developed to detect states of depression, anxiety and emotional distress amongst patients who were being treated for a variety of clinical  problems (Zigmond and Snaith 1983). The scale was not designed to be a clinically diagnostic tool (Whelan-Goodinson et al., 2009). Originally the scale consisted of 8 questions relating to depression and 8 relating to anxiety. Initial findings  indicated one of the items on the depressions scale was weak (r=.11) thus it was removed. Remaining items on the scale had correlations ranging from +.60 to +.30, with a significance of (p<0.02). Anxiety items had correlations ranging from +.76 to +.41 (p<0.01); however, to keep the items in each scale equal, the weakest item on the anxiety portion of the scale was removed. Thus the final scale has a total of 14 items, with responses being scored on a scale of 0-3, with 3 indicating higher symptom frequencies (Whelan-Goodinson et al., 2009). Score for each subscale (anxiety and depression) can range from 0-21 with scores categorized as follows: normal (0-7), mild (8-10), moderate (11-14), severe (15-21). Scores for the entire scale (emotional distress) range from 0-42, with higher scores indicating more distress. Prior to completing the scale patients are asked to “fill it complete in order to reflect how they have been feeling during the past week” (Zigmond and Snaith, 1983; p. 366).

 

Unfortunately within in the TBI population, many measures are used to assess depression and anxiety post injury, but none of these measures have been evaluated for use with this population (Whelan-Goodinson et al., 2009; Schonberger and Ponsford, 2010). Recently the HADS has been tested with those who have sustained an ABI; however due to the mixed aetiology problems were found with some of the questions which could be related to the injury itself, the level of cognitive impairment or the decreased speed at which information is processed (Dawkins et al., 2006; Johnston et al., 2000).

 

Table 17.31 The Hospital Anxiety and Depression Scale (HADS)

Question

Responses

Points

(A)     I feel tense or ‘wound up’:

Most of the time

A lot of the time

From time to time, occasionally

Not at all

3

2

1

0

(D)  I still enjoy the things I used to enjoy:

Definitely as much

Not quiet so much

Only a little

Hardly at all

0

1

2

3

(A)     I get a sort of frightened feeling as if something awful is about to happen:

Very definitely and quiet badly

Yes, but not too badly

A little, but it doesn’t worry me

Not at all

3

2

1

0

(D)   I can laugh and see the funny side of things:

As much as I always could

Not quite so much now

Definitely not so much now

Not at all

0

1

2

3

(A)     Worrying thoughts go through my mind:

A qreat deal of the time

A lot of the time

From time to time but not too often

Only occasionally

3

2

1

0

(D)   I feel cheerful:

Not at all

Not often

Sometimes

Mors of the time

3

2

1

0

(A)      I can sit at ease and feel relaxed:

Definitely

Usually

Not often

Not at all

0

1

2

3

(D)   I feel as if I am slowed down:

Nearly all the time

Very often

Sometimes

Not at all

3

2

1

0

(A)      I get a sort of frightened feeling like ‘butterflies’ in the stomach:

Not at all

Occasionally

Quite often

Very often

0

1

2

3

(D)   I have lost interest in my appearance:

Definitely

I don’t take so much care as I should

I may not take quiet as much care

I take just as much care as ever

3

2

1

0

(A)    I feel restless as if I have to be on the move:

Very much indeed

Quite a lot

Not very much

Not at all

0

1

2

3

(D)   I look forward with enjoyment to things:

As much as ever I did

Rather less than I used to

Definitely less than I used to

Hardly at all

0

1

2

3

(A)    I get sudden feelings of panic

Very often indeed

Quite often

Not very often

Not at all

3

2

1

0

(D)   I can enjoy a good book or radio or TV program

Often

Sometimes

Not often

Very seldom

0

1

2

3

TOTAL SCORE

 

(A)= anxiety related questions; (D)= depression related questions

 

Table 17.32 Characteristics of the HADS

Reliability

Test-retest:Results indicate there is good test-retest reliability on the HADS at 0-2 weeks =.84; >2-6 weeks =73 and >6 weeks 70 for the anxiety subscale. Results from the depression subscale were 0-2 weeks; >2-6 weeks ; and >6 weeks ; indicating the HADS was stable enough to withstand situation influences (Herrmann 1997). Pearson product movement correlation was found to be .92 and .90 between the HADS total score and the HADS anxiety score and the HADS depression score (Herrero et al., 2003).

Inter-Rater Reliability:Kappa scores indicated there was no significant difference between the GHQ-28 and HADS (total score) (kappa statistic =.074, SE=.089, p=o.04).

Internal consistency: Good internal consistency was found ( .80 for the anxiety subscale scale and  .81 for the depression subscale) during initial testing (Zigmond and Snaith, 1983). Whelan-Goodinson et al. (2009) found good internal consistency with Cronbach   scores of .94 on the total HADS score, .88 on the depression subscale and . 92 on the anxiety subscale. On other studies the internal consistency has been found to range from .68 to .93, mean .83 (for the anxiety subscale) and .67 to .90, mean .82 (for the depression subscale) (Bjelland et al., 2002). In an earlier study, Lisspers et al. 1997, found Cronbach  scores for the HADS total score to be .84, for the HADS anxiety subscale, .82 and for the HADS depression subscale .90. Scores in this study were not affected by gender or age. Herrero et al. (2003) found, while validating the scale with a group of Spanish patients, Cronbach    scores to be .90 for the full scale, .84 for the depression subscale and .85 for the anxiety subscale. Subscales also correlated with each other and each subscale correlated with the full scale  .

Validity

Convergent Validity:the correlation between the HADS depression subscale and the Beck Depression Inventory Primary Care (BDI-PC) has been found to be .62, p<0.001 (Beck et al., 1997).

Concurrent Validity: Higher scores on the HADS-depression subscale were linked to higher scores on the SCID–IV (mean=3.52; sd=3.01 and mean=9.29; sd 5.19 respectively; t=6.84, df=98, p<0.001). Of note 38.2% diagnosed as depressed on the SCID-IV scored within the normal range on the HADS-D. Results from the SCID-IV for those diagnosed with an anxiety disorder (mean 11.42, sd 4.75) had a higher mean score on the HADS anxiety subscale (mean 5.37, sd 3.95) (t=6.47, df = 62.41, p=0.000); however 25% tested within the normal range of the HADS anxiety scale. Study authors suggest this was indicative of the time line in which the patient is asked to consider when completing the HADS (Whelan-Goodinson et al., 2009).

Several studies have found that the HADS total score shows a higher correlation with depression and anxiety criterion measures than the subscale do (McDowell, 2006). Lisspers and colleagues (1997) found the correlation with the BDI was .71 for the HADS-depression subscale but for the total HADS the correlation with was .73). For hospital outpatients the HADS-depression subscale correlated .77 with the Montgomery-Asberg Depression Rating (MADR) scale with a group of psychiatric patients (.70). Again with a group of elderly depressed patients the HADS and the MADR correlated .54 and .79. Overall, Mykletun and colleagues (2001) have reported the correlation between the sub-scores and the over all score as reliable.

Discriminant Validity: Correlation between the subscales of the HADS and the correlation between the HADS total score and other scales (the General Health Questionnaire (GHQ-28)) and the MADR scale can vary considerably. Aylard et al (1987) found the correlation of the two subscales of the HADs was  compared to the subscale on the GHQ-28 . Lewis and Wessely (1990) found the correlation between the HAD total score and the GHQ-28 was .75.

Predictive validity: The HAD-depression and anxiety subscales and were found to account for 52.6% and 60% (respectively) of variance when looking at patients who were diagnosed with a mood disorders and those with no psychiatric disorder (Herrero et al., 2003).

Responsiveness

In studies of primary care population, the HADS was successful in detecting DSM-III defined psychiatric morbidity, with the ROC curve showing a score of 8+ being optimal (Bjelland et al., 2006). When using the DSM III clinical interview schedule as the gold standard, ROC curves indicated >/=9 on the HADS anxiety subscale (sensitivity .66 and specificity .93) were indicative of caseness and scores of >/=7 on the HADS depression subscale (sensitivity .66 and specificity .97) were indicative of caseness. (Bjelland et al., 2006). Beck et al., (1997) found the HADS depression subscale had a AUR of .74 (SE =.09) with a cut off score of >/=5 yielding the highest efficiency at 72% with a sensitivity of 85%, but the specificity of only 47%. According to Herrero et al (2003), the curve ROC shows the model discriminates between cases and non cases: HAD-D (area-0.887; 95%CI: 0.84 to 0.91), HAD-A (area-.917; 95%CI: 0.88.to 0.95). For each of these two subcales the predicative power is 80% (HAD-D) and 83% (HAD-A). For the full scale the predicative power is 81%. Herrmann (1997) found the HADS correlated well with other quality of life indicators used in a variety of studies looking at patients with HIV, renal insufficiency, etc. the HADS anxiety subscale correlated well with chest pain, tachycardia, dizziness, etc. The HADS depression subscale correlated well with dyspnea, low exercise tolerance etc. 

Tested for ABI/TBI patients?* 

Yes the scale has been tested with an ABI population.

Other Formats

The scale has been translated into Arabic (Malasi et al., 1991), Dutch, French, German, Hebrew, Swedish, Italian and Spanish. All are available at no cost (Zigmond and Snaith, 1983). Recently a computer administered version using a touch screen has been developed and has been found to be as valid as the paper and pencil version (McDowell 2006).

Use by Proxy?

The scale is designed to be completed by the individual.

 


Advantages: The HADS is brief and simple to use and although it was originally designed to be used with hospital populations it has been found to perform well with non-hospital groups (McDowell, 2006).It has been found to take on average 2-5 minutes to complete and is completed by the patients themselves (Snaith, 2003). The HADS requires the individual to respond to the question in relation to how they felt in the past week, thus it is therefore reasonable to re-administer the test again but only at weekly intervals. It has been found to perform as well as the BDI and the GHQ instruments.  Overall, Mykletun et al. (2001) found the HADS scale possessed good “psychometric properties in terms of factor structure, intercorrelation, homogeneity and internal consistency” (p 543).

Limitations: When using the HADS to diagnosis depression or depressive symptoms post ABI, the sequelae of TBI may confound the test scores (Whelan-Goodinson et al., 2009). Caution is recommended when interpreting the results of these scales (Dawkins et al., 2006). Even though the HADS has been shown to be a reliable measure of emotional distress post ABI, the cut off scores and categories have not been shown to be useful in predicting probable presence or “caseness” of depression or anxiety (Whelan-Goodinson et al., 2009).

 

Summary – HADS

Interpretability: The results are easy to interpret with higher scores on each individual scale or the entire scale indicating greater anxiety, depression or mood disorders.

Acceptability: The HADS is widely accepted and used with most patient populations including those with a TBI.

Feasibility: The scale is readily available and can be used free of charge. It takes only a few minutes to complete, no specialized training is need to administer the test and may be completed by the patients themselves.



 

Table 17.33 HADS Evaluation Summary

Reliability

 

Validity

Responsiveness

Rigor

Results

Rigor

Results

Rigor

Results

Floor/ceiling

+++

+++ (IC)

+++ (TR)

+++

+++(CV)

++ (CV-D)

+++ (DV)

+++

+++

N/A

NOTE: +++=Excellent; ++=Adequate; +=Poor; N/A = insufficient information; TR=Test re-test; IC= internal consistency; IO = Interobserver;