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Dentists’ ability to detect psychological problems in patients with temporomandibular disorders and chronic pain
j m R E S E A R C H
a R E P O R T S
Do patients with temporomandibular disorders (TMD) have significant psychosocial problem s ? Research efforts have sought to determine if these problems exist, and if so, how they influence treatment outcome. Even when psychosocial factors do influence treatment outcome, identifying them by form al psychological tests can be time consuming and costly. Dentists’ impressions of the psychological status of these patients were tested to determine if they are an effective method for screening psychological factors thought to influence treatment outcome. The results suggested that a screening procedure based on dentists’ impressions from an initial examination do not adequately identify psychological problems in patients with TMD.
Dentists’ ability to detect psychological problems in patients with temporomandibular disorders and chronic pain M a rk E. O a k le y , P h D C h a rle s P . M c C rea ry , P h D V ir g in ia F . F la c k , P h D
G le n n T . C la r k , D D S , M S W illia m K. S o lb e rg , D D S, M SD A n d re w G . P u llin g e r , D D S , M Sc
here is evidence th a t early iden tification and treatm ent of psy chological problem s in persons w ith h ealth problem s can dim in ish the use a n d cost of m edical services in prepaid m e d ic a l p l a n s . 1,2 A n e v a lu a tio n of a psychiatric p la n (Blue Cross) has revealed s im ila r f in d in g s in th e fee-for-service p riv ate secto r.3 T h erefo re, id e n tify in g an d p ro v id in g tre a tm e n t for p a tie n ts un d erg o in g m edical care w ho also have psychological problem s is desirable. T h is w o u ld id e n tify p a tie n ts w h o , because of psychosocial difficulties, are n o t likely to respond to conventional m edical care for TM D , and w ould provide treatm ent p la n s th a t a d d re ss p a t ie n t s ’ re le v a n t psychosocial problem s. However, n o established m ethod exists to id e n tify p sy c h o lo g ic a l p ro b le m s in a te m p o r o m a n d ib u la r d iso rd e r p o p u lation. A lth o u g h psychological tests have
differentiated between p o o r versus good o u tc o m e g ro u p s , these d ifferen ces are not strong en o u g h to predict individual tre a tm e n t o u tc o m e .4 O th e r re p o rts 4 of T M D have suggested a need for further research to identify psychological factors th a t c h a ra c te riz e th e n o n r e s p o n d in g p atien t.4 A lth o u g h th e use o f s ta n d a rd iz e d p s y c h o lo g ic a l tests h as th e a d v a n ta g e of relatively reliable and valid m easure m ent instrum ents, use of these tests may be im p ra ctic al for p atien ts in term s of tim e a n d cost. Also, dentists m ay be able to d e te c t th e p sy c h o lo g ic a l d is o rd e r re la te d to o u tc o m e w ith o u t n ee d for form al testing. A rev ie w o f th e lite r a tu r e fa ile d to produce any studies th at com pare dentists’ c lin ic a l im p re ssio n s (tak e n d u r in g an in it ia l e x a m in a tio n ) to p sy c h o lo g ic a l test results in a TM D p o p u latio n . Some
T
studies have investigated the p h y sician ’s a b ility to a c c u ra te ly id e n tify p s y c h o lo g ic a l p ro b le m s u s in g p sy c h o lo g ic a l tests or psychiatric interviews. O ne such study of 526 m edical o u tp a tie n ts co m pared diagnoses of depression based on th e Beck D e p re s s io n In v e n to ry (B D I) w ith physicians’ identification of depres sion recorded in a m edical ch art.5 T hese a u th o r s fo u n d th a t th e c o n d itio n s of slightly m ore th an h alf of p atien ts rated d e p re s se d by th e B D I o r th r o u g h a p s y c h ia tric in te rv ie w w ere u n d e te c te d by th e ir p h y sician s. F u rth erm o re, p h y sicians d id n o t seem to recognize patien ts w ho were m ore seriously depressed. O ne m ethodological shortcom ing of the study by N ielson an d W illiam s5 was the reliance on ch a rt notes to assess re c o g n itio n of d e p r e s s io n — th e p h y s ic ia n s m ay h av e perceived, b u t n o t recorded depression, because of its irrelevance to the disorder JADA, Vol. 118, Ju n e 1989 ■ 727
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for w hich the p atien t sought treatm ent. In a sim ilar fin d in g of patients w ith p s y c h ia tric p ro b le m s ( r a n g in g fro m m in o r to severe), 27.5% of the w om en an d 19% of the m en were n o t so identified by th eir general practitio n ers.6 F u rth e r m o re , p r a c titio n e r s ’ d ia g n o s e s w ere characterized by h ig h false-positive rates. O f p a tie n ts id e n tifie d by p sy c h ia trists as n o t h a v in g p s y c h ia tric d iso rd e rs, g en e ral p ra c titio n e rs d ia g n o sed a psy ch iatric disorder in 59.4% of males and 47% of females. G oldberg a n d o th ers7 fo u n d th a t the co rrela tio n betw een p h y sic ia n s’ ratin g s an d the G eneral H e a lth Q u estio n n aire (G H Q ) was statistically sig n ific an t but low (r = .34). T h ere were no differences in p h y s ic ia n s ’ a b ility to id e n tify p s y c h o lo g ic a l p ro b le m s o f th e ir p a tie n ts in relation to their year of train in g .7 K nights and F olstein8 reported a 35% false-negative rate for psychiatric sym p tom s by staff p h y sic ia n s in a study of hospitalized m edical patients. Hesbacker and cow orkers9 com pared prim ary p h y sicians’ rec o g n itio n of psychopathological conditions w ith patien ts’ self-ratings o n th e S y m p to m C h e c k list (SC L). O f those p atients rated as severely im paired on the SCL, 33% were n o t so recognized by th eir fam ily physicians. T h e corres p o n d in g r a te of false n e g a tiv e s w ith m oderate im p a irm e n t o n the SCL was 65%. T h e re is n o evidence th a t c lin ic ia n s are able to detect psychological disorders in m edical ou tp atien ts w ith a h ig h degree of accuracy. M ethodological weaknesses of earlier investigations include: —Q u e stio n a b le “ g old sta n d a rd ” c r i teria for determ ination of psychological problem s (for exam ple, overreliance on s in g le m e asu res o f g lo b a l p sy c h ia tric dysfunction)5,8-9; —U se of p h y sic ia n ratin g s of global p s y c h ia tric d is tu rb a n c e (fo r ex a m p le , r a tin g s b a s e d o n a s e v e n -p o in t scale r a n g in g fro m p s y c h ia tric d is tu rb a n c e “ n o t p rese n t” to “ extrem ely severe” or sim ply asking “ Does your p atien t have a psychiatric problem ?” ).8,9 It is possible th a t p h y s ic ia n s c a n a c c u ra te ly d etec t certain psychological problem s (anxiety), b u t n ot others (depression); — U se of m e d ic a l rec o rd s fo r d e te r m in in g physician recognition of disorder (for exam ple, depression may have been perceived b u t n o t recorded).5 T h is study seeks to avoid these m ethod olo g ical p itfa lls by m e a su rin g p sy ch o logical disorders com prehensively, using m u ltip le m e a su re s; o b ta in in g d ire c t 728 ■ JADA, Vol. 118, Jun e 1989
m easures of clin ician s’ ju d g m en ts regard in g se v eral a s p e c ts of p s y c h o lo g ic a l dysfunction after an in itial exam ination; directly co m p arin g clin ician s’ judgm ents to psychological test scores; an d extending this lin e of research to the psychosocial variables of stress, anxiety, denial, an d depression in a T M D p o p u la tio n . Spe cifically, this study uses den tists’ clinical im p ressio n s based o n an in itia l ex am in a tio n (w ith o u t ex p lo rin g psychosocial factors o r seeing the results of psycho logical testing) as a screening procedure to id e n tify p sy c h o lo g ic a l p ro b lem s in a TM D p o p u latio n . T w o p r o p e r tie s fo r e v a lu a tin g an y screening procedure are the p ro b ab ility of d e c la rin g in d iv id u a ls w h o do have the disorder as positive (the probability o f r a tin g a tru e p o s itiv e as p o sitiv e ), an d the prob ab ility of declaring “n o rm al” in d iv id u a ls as n o t h a v in g the disorder in q u e s tio n (th e p ro b a b ility of ra tin g a tr u e n e g a tiv e as a n e g a tiv e ). T h e se p ro b a b ilitie s are se n sitiv ity a n d sp e ci ficity, respectively.10 T h is in v e stig a tio n estim ates the sen sitivity an d specificity of dentists’ clinical im p re s s io n s as a sc re e n in g p ro c e d u re to id e n tify p sy c h o lo g ic a l p ro b lem s in a T M D p o p u la tio n . C rite ria based o n sta n d a rd iz e d p sy c h o lo g ic a l tests serve as th e g o ld s ta n d a r d in th is stu d y . D entists’ clinical im pressions are derived from an in itia l dental exam ination and interview , w ith o u t system atically explor
1. Do you think this patient is depressed? Yes or No If yes, rate severity: 1 2 mild
in g p s y c h o so c ia l p ro b le m s o r h a v in g access to psychological test results. Methods Subjects
P a tie n ts w ith T M D fro m th e U C L A T e m p o ro m a n d ib u la r a n d F acial P a in C linic w ho reported m usculoskeletal pain in the trig em in al region as the prim ary p ro b le m (N = 107), w ere th e su b je cts of this investigation. B efore tr e a tm e n t, a ll p a tie n ts w ere given psychological tests w hich included the M in n eso ta M u ltip h asic P erso n ality Inventory (M M P I,11 the BD I,12 the Sched ule of R ecent E x p erien ce (SR E ),13 an d th e S ta te - T r a it A n x ie ty In v e n to ry (S T A I).14 W hen testin g was com pleted, p a tie n ts w ere sc h e d u le d fo r a d e n ta l e x a m in a tio n . A fter th a t e x a m in a tio n , w ith o u t access to results of psychological testing, faculty d entists from the clinic w ere asked to in d icate th e presence or absen ce of d e p re ssio n , a n x ie ty , recen t stress, an d d enial on a L ikert scale. T h e q u estio n n aire used by the dentists is show n in F igure 1. T h e sensitivity an d specificity estimates of the d entists’ L ikert scale ratings were com puted as follow s. A d en tist’s ratin g of 0 was regarded as a negative finding an d a score of 1 or greater was regarded as a positive fin d in g . T hese were com p are d w ith th e fin d in g s based on psy-
3
moderate
5 severe
moderate
2. Do you characterize this patient as being anxious or tense? Yes or No If yes, rate severity: 1 2 3 mild
4
4
5 severe
3. Do you think this patient has experienced a lot of stressful situations during the past year? Yes or No 4 5 If yes, rate severity: 1 2 3 mild
moderate
severe
4. Do you think this patient exhibits defensiveness and denial (minimizing problems in life such as stress, or interpersonal conflict)? Yes or No If yes, rate severity: 1 2 3 4 5 mild
moderate
severe
Fig 1 ■ Questionnaire using Likert scale given to dentists after examining study subject.
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ch o lo g ic a l test scores. S e n sitiv ity w as c o m p u te d by d iv id in g th e n u m b e r of people rated positive, b o th by d en tists’ r a tin g s a n d p sy c h o lo g ic a l te s tin g , by the total num ber of persons rated positive ac co rd in g to p sy c h o lo g ic al test scores. T h is fra c tio n is m u ltip lie d by 100 to y ield a p erc en ta g e. S p e c ific ity is also expressed as a percentage an d is com puted by dividing the n um ber of people rated neg ativ e b o th by d e n tis ts ’ ra tin g s a n d psych o lo g ical testing, an d by the total n u m b e r of p e o p le r a te d n e g a tiv e by psychological testing. Results D e n tis ts ’ c lin ic a l im p r e s s io n s o f th e p re se n c e o r ab sen c e o f p s y c h o lo g ic a l p ro b lem s w ere co m p ared w ith criteria based on standardized psychological tests th a t served as the g old standard. G old sta n d a rd crite ria w ere based o n cuto ff scores th a t corresp o n d w ith com m only accepted clin ic al th re sh o ld s of distress for the p ertinent psychological variable. T h e exception to this ru le was state and trait anxiety in w hich the gold standard was d efin ed as scores g rea ter th a n the 83rd p ercen tile. T h is co rresp o n d s to a sco re 1 s ta n d a r d d e v ia tio n ab o v e th e mean. T h e g o ld sta n d a rd c rite ria a n d c o r re s p o n d in g base ra te s fo r ea ch of the p s y c h o lo g ic a l v a ria b le s in th is T M D sam ple are as follow s: depression (BDI > 9) = 28%; state a n x ie ty (S T A I > 83 p e rc e n tile ) = 24%; tr a it a n x ie ty (ST A I > 83 percentile) = 38%; recent life stress (SRE > 300) = 53%; denial (M M PI K > 70T) = 7%. T h e m eans, sta n d a rd devi ations, an d ranges for psychom etric scores observed in this T M D sam ple are p re sented in T ab le 1. S ensitivity a n d spe cificity were co m p u ted for each of the psychological variables rated by dentists. T h e results of these analyses are presented in T ab le 2, sh o w in g sen sitivity ranges fro m 88% for state an x iety , to 56% for d e n ia l; a n d s p e c ific ity ra n g e s fro m a low of 19% for state anxiety to a h ig h of 58% for denial. Also, the ratings w ith th e h ig h e s t s e n s itiv ity h a d e x tre m e ly low specificity. C o m p u tin g sensitivity an d specificity in v o lv e s d ic h o to m iz in g th e d e n tis ts ’ ratings in terms of the presence o r absence of th e v a rio u s p s y c h o lo g ic a l fac to rs. D e n tists ’ ra tin g s can also be reg ard ed in a m ore c o n tin u o u s fash io n a n d are co m p ared w ith the p sy c h o m e tric g o ld sta n d ard by c o m p u tin g a P earso n cor r e la tio n c o e ffic ie n t. T h e c o r r e la tio n s
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Table 1 ■ Means, standard deviations, and ranges for psychometric scores. Variable
Mean
SD
Range
N
Age Beck depression inventory STAI-state anxiety STAI-trait anxiety SRE-life stress rating MMPI-K Scale (denial)
40.7 8.71 53.74 59.46 479.74 56.50
12.0 8.40 32.74 33.71 437.22 8.36
19-64 0-41 2-100 0-100 0-2511 36-79
107 107 104 104 97 107
Table 2 ■ Sensitivity and specificity estimates for dentists’ ratings of psychological variables (gold standard = psychological test scores). Variable Dentist anxiety rating (trait) Dentist anxiety rating (state) Dentist life stress rating Dentist depression rating Dentist defensive/ denial rating
Sensitivity
n
Specificity
n
Gold standard base rate
80%
40
19%
65
38
88%
25
21%
80
24
84%
50
27%
45
53
74%
39
56%
68
28
53%
36
58%
71
34
betw een d e n tis ts ’ ra tin g s a n d th e c o r re sp o n d in g psy ch o lo g ical test for each p sy c h o lo g ic a l v aria b le are: d ep ressio n (.20), state a n x ie ty (.12), tr a it a n x ie ty (.08), d e f e n s iv e n e s s /d e n ia l (.02), a n d recent life stress (.34). T h e e x te n t of a g re e m e n t b etw e en d en tists’ ratin g s an d p sychological test g o ld s ta n d a rd s w as also e s tim a te d by c o m p u tin g k,15 as su m in g h o m o g en eity of d e n tis ts ’ r a tin g s d is trib u tio n s . T h e resu lts of these analyses are p resen ted in T able 3. It co u ld be a rg u e d th a t th e rela tiv e “cost” of false-positive or false-negative ratings depends on the extent of actual p s y c h o p a th o lo g ic a l c o n d itio n s in a p a r tic u la r p a tie n t. T h a t is, a falsenegative ra tin g w o u ld be m ore serious w hen the actual psy ch o p ath o lo g ic co n d itio n is severe th a n if it w ere m ild . T h e re fo re , a w e ig h te d k a n a ly sis w as com puted th a t assigns a heavier w eight to cases in w hich the discrepancy between the gold standard an d the dentists’ ratings are larger. W eights p ro p o rtio n a l to the distance from the d iagonal of the m atrix of r a te r a g re e m e n ts w ere u s e d .15 T h e results of these analyses are also presented in T a b le 3, sh o w in g th a t th e level of ag reem ent betw een d en tist ratin g s an d psychom etric gold standards are low for the w eighted k analyses. An u n w eig h t ed analysis (not show n) yielded sim ilar results. k
Discussion D entists’ ratin g s as a screening procedure h ad low sp ecificity for a ll of th e p sy chological factors, a n d corresponded to m isclassifying from 44% (depression) to 81% (state anxiety) of the true negatives. R e g a rd in g sen sitiv ity , d e n tis ts ’ ra tin g s of depression, d en ial, an d tra it anxiety w ere re la tiv e ly u n s e n sitiv e a n d c o rre sponded to m isclassifying from 20% (trait a n x ie ty ) to 47% (d e n ia l) o f th e tru e p o sitiv es. D e n tis ts ’ r a tin g s w ere m o st sensitive for state anxiety (88%) an d life stress (84%). H ow ever, these h ig h se n sitivity values were offset by low spec ificity values (19% an d 27%, respectively). A lso, th e re w ere n o la rg e c o rre la tio n s betw een d e n tists ’ ra tin g s a n d th e g o ld standard m easures of depression, anxiety, denial, o r recent life stress. Furtherm ore, an a ly se s in d ic a te d th a t th e level of agreem ent between den tists’ ratings and categorized psychological test gold stan d ard s w ere low . T h e se resu lts su g g est th a t a s c re e n in g p ro c e d u re b a s e d o n d e n tis ts ’ g lo b a l im p r e s s io n s fro m an in itia l e x a m in a tio n do n o t ad e q u ately id e n tify p s y c h o lo g ic a l p ro b le m s in a T M D p o p u latio n . T h e values of sensitivity an d specificity are affected by th e cu to ffs ch o se n fo r d e n tist ra tin g s a n d p sy c h o m etric g o ld s ta n d a rd s . F o r e x a m p le , r a th e r th a n choosing a d en tist ra tin g > 1 as a positive, k
Oakley-Others : PSYCHOLOGICAL PROBLEMS IN PATIENTS W ITH TM DISORDERS ■ 729
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Ta b le 3 ■ Extent of agreem ent betw een d e n tis ts ’ ratings and psychological test gold standards: weighted kanalyses. Weighted Psychological variable Depression Anxiety (state) Anxiety (trait) Recent life stress Defensive denial
Agreement k
SD (K )
(%)
Chance (%)
0.21 0.52 0.54
0.07 0.04 0.54
0.68 0.49 0.53
0.59 0.46 0.50
0 .1 1
0.09
0.57
0.52
0.07
0.07
0.65
0.63
ratings > 3 could have been used as the c u to ff fo r p o s itiv e in d ic a tio n s o f th e p a r tic u la r d iso rd e r. T h is w o u ld have the effect of increasing specificity w hile p ro d u c in g a co rresp o n d in g decrease in sensitivity. U sin g d e n tists’ ratin g s > 0 as the cutoff has the effect of m axim izing sen sitiv ity. In th is study, sensitivity is the m ost im p o rta n t issue. T h e ratings dentists give patients could be regarded as a first step in screening; those individuals w ho are rated positive by d e n tists can be referred for follow u p e v a lu a tio n u sin g stan d ard ized psy chological tests. However, in this study, th at decision w ould have resulted in m any in d iv id u a ls b e in g re fe rre d for te stin g w ho did n o t need it. A related issue is the u n k n o w n sub jective fram e of reference that the dentists w ere u s in g w h en m a k in g ratin g s. T h e w eighted analyses provide no evidence th a t d e n tis ts ’ a g re e m e n t w ith p sy c h o m e tric g o ld s ta n d a r d s im p ro v e s w ith in c re a s in g severity of d e n tists’ ra tin g s o r psychom etric criteria. In a d d itio n , p sy ch o lo g ical p roblem s m ay n o t be obvious or reliably detected by im p re ssio n s from a n in itia l e x a m ination. T h is has im p o rta n t im plications for th e tim in g of q u e s tio n s re g a rd in g p sych o logical status. T herefore, if psy chological status is p u rsued only w hen th e c l in ic ia n th in k s th e re m ay be a problem , m any psychological problem s w ill go u n d etec ted . I t is p o ssib le th a t d en tists co u ld m ore accurately identify psychological problem s in a TM D p ain p o p u la tio n if they placed m ore em phasis on system atically exploring psychological distress in the in itial dental exam ination an d m edical interview , o r if they were train ed to identify psychological p ro b lems. T h e p s y c h o lo g ic a l tests th a t served as the g old standard criteria in this study a re a su b se t of o th e r tests th a t c o u ld also be used as gold standards. Therefore, k
730 ■ JADA, Vol. 118, June 1989
k
conclusions can n o t be generalized beyond th e set o f p s y c h o lo g ic a l tests u sed in this study. Also, the psychological tests used in this study have lim itations shared w ith m a n y p sy c h o lo g ic a l tests. F or exam ple, a p atien t could respond falsely or random ly. These concerns are partially addressed in th e v a lid ity scales of the MMPI. M M PI scores of K > 70T have been su g g e ste d to in d ic a te d e fe n s iv e n e s s / d e n ia l,1618 an d in the case of test-taking, the tendency to fake good (for exam ple, present oneself in a favorable way w hen conditions are n o t favorable).17 T h e use of k as a m easure of denial in th is study m ust be qualified in th at it is a com plex m e asu re of m an y o th e r factors. It has been su g g ested to be an in d ic a tio n of efforts to a p p e a r ad eq u ate, in co n tro l, and effective, as well as to reflect serious lim ita tio n s in p e rs o n a l in s ig h t a n d u n d erstan d in g .18 Conclusions T h e psychological factors studied in this investigation are am ong several of interest in the T M D p o p u la tio n . F u tu re inves tig a tio n s co u ld focus o n o th er psy ch o logical factors such as hypochondriasis, hysteria, or an g er/h o stility . Finally, these r e s u lts do n o t im p ly e n d o rs e m e n t o f p s y c h o lo g ic a l te s tin g w ith a ll T M D patients as the p articu lar variables studied in this investigation have yet to be proved as c o n s is te n tly re la te d to tr e a tm e n t o utcom e. A d d itio n al in v estig atio n s are needed. -----------------------J!SOA\ ----------------------This research was supported by NIDR grant no. DE07618. Dr. Oakley is assistant clinical professor of psychiatry and biohavioral sciences, School of Medicine; Dr. McCreary is clinical professor, School of Medicine, department of biobehavioral sciences; Dr. Flack is assistant professor, School of Public
Health, division of biostatistics; Dr. Clark is professor, School of Dentistry; Dr. Solberg is professor, School of Dentistry; and Dr. Pullinger is associate professor, School of Dentistry, University of California. Address requests for reprints to Dr. Oakley at University of California, Los Angeles, UCLA Dental Research Institute, Center for the Health Sciences, 73-029, Los Angeles, 90024-1762. 1. Follet W, Cummings NA. Psychiatric services and medical utilization in a prepaid health plan setting. Med Care 1967;5:25-35. 2. Goldberg ID, Krantz G, Locke BZ. Effect of a short term outpatient psychiatric therapy benefit on the utilization of medical services in a pre-paid group-practice medical program . Med Care 1970;5:419-28. 3. Jameson J, Shuman LJ, Young WW. The effects of outpatient psychiatric utilization on the costs of providing third party coverage. Philadelphia: Blue Cross of Western Pennsylvania, 1976; research series 18. 4. Olson RE. Behavioral examinations in MPD. In: The president’s council on the exam ination, diagnosis, and management of temporomandibular disorders. Chicago: American Dental Association, 1983; 104-5. 5. Nielson AC, W illiams TA. Depression in ambulatory medical patients: Prevalence by selfreport questionnaire and recognition by non psychiatric physicians. Arch Gen Psychiatry 1982;37:999-1004. 6. Eastwood MK. Screening for psychiatric dis orders. Psychol Med 1971; 197-208. 7. Goldberg DP, Cooper B, Eastwood MR, Kedward HB, Shepard M. A standardized psychiatric interview for use in community surveys. Br J Prev Soc Med 1970;24:18-23. 8. Knights EB, Folstein MF. Unsuspected emo tional and cognitive disturbance in medical patients. Ann Intern Med 1977;87:723-4. 9. Hesbacker PT, Rickels K, Goldberg D. Social factors and neurotic symptoms in family practice. Am J Public Health 1975;65:148-55. 10. Morton RF, Hebei JR. A study guide to epidemiology and biostatistics. Baltimore: University Park Press, 1979. 11. Minnesota Multiphasic Personality Inventory, copyright 1943 [Psychological test]. The Univ of Minn Nat Comput Syst Inc, PO Box 1416, Min neapolis, 55440. 12. Beck AT. The Beck Depression Inventory, copyright 1978. [Psychological test]. Center for cognitive therapy, Room 602, 133 S 36th St, Philadelphia, 19104. 13. Holmes TH, Rahe RH. The social readjust ment rating scale. [Psychological test]. J Psychosom Res 1967;11:213-8. 14. Speilberger LD, Goruch RL, Lushe R, Vagg PR, Jacobs GA, copyright 1968, 1977 by Charles P. Spielberger. [Psychological test]. Consulting Psychologists Press, 577 College Ave, Palo Alto, CA 94306. 15. Fleiss JL. Statistical methods for rates and proportions. 2nd ed. New York: Wiley 8c Sons, Inc, 1981:222-5. Weighted kappa: eq. 13.29. Standard deviation: eq. 13.36. Weights proportional to distance: eq. 13.31. 16. Lachar D. The MMPI: Clinical assessment and automated interpretation. Los Angeles: Western Psychological Services, 1974:3. 17. Graham JR. The MMPI: a practical guide. 2nd ed. New York: Oxford University Press, 1987:25-
8. 18. Dahlstrom WH, Welsh GS, Dahlstrom LE. An MMPI handbook. Volume 1: Clinical inter pretation. Minneapolis: University of Minnesota Press, 1967:166.
a R E P O R T S
Do patients with temporomandibular disorders (TMD) have significant psychosocial problem s ? Research efforts have sought to determine if these problems exist, and if so, how they influence treatment outcome. Even when psychosocial factors do influence treatment outcome, identifying them by form al psychological tests can be time consuming and costly. Dentists’ impressions of the psychological status of these patients were tested to determine if they are an effective method for screening psychological factors thought to influence treatment outcome. The results suggested that a screening procedure based on dentists’ impressions from an initial examination do not adequately identify psychological problems in patients with TMD.
Dentists’ ability to detect psychological problems in patients with temporomandibular disorders and chronic pain M a rk E. O a k le y , P h D C h a rle s P . M c C rea ry , P h D V ir g in ia F . F la c k , P h D
G le n n T . C la r k , D D S , M S W illia m K. S o lb e rg , D D S, M SD A n d re w G . P u llin g e r , D D S , M Sc
here is evidence th a t early iden tification and treatm ent of psy chological problem s in persons w ith h ealth problem s can dim in ish the use a n d cost of m edical services in prepaid m e d ic a l p l a n s . 1,2 A n e v a lu a tio n of a psychiatric p la n (Blue Cross) has revealed s im ila r f in d in g s in th e fee-for-service p riv ate secto r.3 T h erefo re, id e n tify in g an d p ro v id in g tre a tm e n t for p a tie n ts un d erg o in g m edical care w ho also have psychological problem s is desirable. T h is w o u ld id e n tify p a tie n ts w h o , because of psychosocial difficulties, are n o t likely to respond to conventional m edical care for TM D , and w ould provide treatm ent p la n s th a t a d d re ss p a t ie n t s ’ re le v a n t psychosocial problem s. However, n o established m ethod exists to id e n tify p sy c h o lo g ic a l p ro b le m s in a te m p o r o m a n d ib u la r d iso rd e r p o p u lation. A lth o u g h psychological tests have
differentiated between p o o r versus good o u tc o m e g ro u p s , these d ifferen ces are not strong en o u g h to predict individual tre a tm e n t o u tc o m e .4 O th e r re p o rts 4 of T M D have suggested a need for further research to identify psychological factors th a t c h a ra c te riz e th e n o n r e s p o n d in g p atien t.4 A lth o u g h th e use o f s ta n d a rd iz e d p s y c h o lo g ic a l tests h as th e a d v a n ta g e of relatively reliable and valid m easure m ent instrum ents, use of these tests may be im p ra ctic al for p atien ts in term s of tim e a n d cost. Also, dentists m ay be able to d e te c t th e p sy c h o lo g ic a l d is o rd e r re la te d to o u tc o m e w ith o u t n ee d for form al testing. A rev ie w o f th e lite r a tu r e fa ile d to produce any studies th at com pare dentists’ c lin ic a l im p re ssio n s (tak e n d u r in g an in it ia l e x a m in a tio n ) to p sy c h o lo g ic a l test results in a TM D p o p u latio n . Some
T
studies have investigated the p h y sician ’s a b ility to a c c u ra te ly id e n tify p s y c h o lo g ic a l p ro b le m s u s in g p sy c h o lo g ic a l tests or psychiatric interviews. O ne such study of 526 m edical o u tp a tie n ts co m pared diagnoses of depression based on th e Beck D e p re s s io n In v e n to ry (B D I) w ith physicians’ identification of depres sion recorded in a m edical ch art.5 T hese a u th o r s fo u n d th a t th e c o n d itio n s of slightly m ore th an h alf of p atien ts rated d e p re s se d by th e B D I o r th r o u g h a p s y c h ia tric in te rv ie w w ere u n d e te c te d by th e ir p h y sician s. F u rth erm o re, p h y sicians d id n o t seem to recognize patien ts w ho were m ore seriously depressed. O ne m ethodological shortcom ing of the study by N ielson an d W illiam s5 was the reliance on ch a rt notes to assess re c o g n itio n of d e p r e s s io n — th e p h y s ic ia n s m ay h av e perceived, b u t n o t recorded depression, because of its irrelevance to the disorder JADA, Vol. 118, Ju n e 1989 ■ 727
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REPORTS
for w hich the p atien t sought treatm ent. In a sim ilar fin d in g of patients w ith p s y c h ia tric p ro b le m s ( r a n g in g fro m m in o r to severe), 27.5% of the w om en an d 19% of the m en were n o t so identified by th eir general practitio n ers.6 F u rth e r m o re , p r a c titio n e r s ’ d ia g n o s e s w ere characterized by h ig h false-positive rates. O f p a tie n ts id e n tifie d by p sy c h ia trists as n o t h a v in g p s y c h ia tric d iso rd e rs, g en e ral p ra c titio n e rs d ia g n o sed a psy ch iatric disorder in 59.4% of males and 47% of females. G oldberg a n d o th ers7 fo u n d th a t the co rrela tio n betw een p h y sic ia n s’ ratin g s an d the G eneral H e a lth Q u estio n n aire (G H Q ) was statistically sig n ific an t but low (r = .34). T h ere were no differences in p h y s ic ia n s ’ a b ility to id e n tify p s y c h o lo g ic a l p ro b le m s o f th e ir p a tie n ts in relation to their year of train in g .7 K nights and F olstein8 reported a 35% false-negative rate for psychiatric sym p tom s by staff p h y sic ia n s in a study of hospitalized m edical patients. Hesbacker and cow orkers9 com pared prim ary p h y sicians’ rec o g n itio n of psychopathological conditions w ith patien ts’ self-ratings o n th e S y m p to m C h e c k list (SC L). O f those p atients rated as severely im paired on the SCL, 33% were n o t so recognized by th eir fam ily physicians. T h e corres p o n d in g r a te of false n e g a tiv e s w ith m oderate im p a irm e n t o n the SCL was 65%. T h e re is n o evidence th a t c lin ic ia n s are able to detect psychological disorders in m edical ou tp atien ts w ith a h ig h degree of accuracy. M ethodological weaknesses of earlier investigations include: —Q u e stio n a b le “ g old sta n d a rd ” c r i teria for determ ination of psychological problem s (for exam ple, overreliance on s in g le m e asu res o f g lo b a l p sy c h ia tric dysfunction)5,8-9; —U se of p h y sic ia n ratin g s of global p s y c h ia tric d is tu rb a n c e (fo r ex a m p le , r a tin g s b a s e d o n a s e v e n -p o in t scale r a n g in g fro m p s y c h ia tric d is tu rb a n c e “ n o t p rese n t” to “ extrem ely severe” or sim ply asking “ Does your p atien t have a psychiatric problem ?” ).8,9 It is possible th a t p h y s ic ia n s c a n a c c u ra te ly d etec t certain psychological problem s (anxiety), b u t n ot others (depression); — U se of m e d ic a l rec o rd s fo r d e te r m in in g physician recognition of disorder (for exam ple, depression may have been perceived b u t n o t recorded).5 T h is study seeks to avoid these m ethod olo g ical p itfa lls by m e a su rin g p sy ch o logical disorders com prehensively, using m u ltip le m e a su re s; o b ta in in g d ire c t 728 ■ JADA, Vol. 118, Jun e 1989
m easures of clin ician s’ ju d g m en ts regard in g se v eral a s p e c ts of p s y c h o lo g ic a l dysfunction after an in itial exam ination; directly co m p arin g clin ician s’ judgm ents to psychological test scores; an d extending this lin e of research to the psychosocial variables of stress, anxiety, denial, an d depression in a T M D p o p u la tio n . Spe cifically, this study uses den tists’ clinical im p ressio n s based o n an in itia l ex am in a tio n (w ith o u t ex p lo rin g psychosocial factors o r seeing the results of psycho logical testing) as a screening procedure to id e n tify p sy c h o lo g ic a l p ro b lem s in a TM D p o p u latio n . T w o p r o p e r tie s fo r e v a lu a tin g an y screening procedure are the p ro b ab ility of d e c la rin g in d iv id u a ls w h o do have the disorder as positive (the probability o f r a tin g a tru e p o s itiv e as p o sitiv e ), an d the prob ab ility of declaring “n o rm al” in d iv id u a ls as n o t h a v in g the disorder in q u e s tio n (th e p ro b a b ility of ra tin g a tr u e n e g a tiv e as a n e g a tiv e ). T h e se p ro b a b ilitie s are se n sitiv ity a n d sp e ci ficity, respectively.10 T h is in v e stig a tio n estim ates the sen sitivity an d specificity of dentists’ clinical im p re s s io n s as a sc re e n in g p ro c e d u re to id e n tify p sy c h o lo g ic a l p ro b lem s in a T M D p o p u la tio n . C rite ria based o n sta n d a rd iz e d p sy c h o lo g ic a l tests serve as th e g o ld s ta n d a r d in th is stu d y . D entists’ clinical im pressions are derived from an in itia l dental exam ination and interview , w ith o u t system atically explor
1. Do you think this patient is depressed? Yes or No If yes, rate severity: 1 2 mild
in g p s y c h o so c ia l p ro b le m s o r h a v in g access to psychological test results. Methods Subjects
P a tie n ts w ith T M D fro m th e U C L A T e m p o ro m a n d ib u la r a n d F acial P a in C linic w ho reported m usculoskeletal pain in the trig em in al region as the prim ary p ro b le m (N = 107), w ere th e su b je cts of this investigation. B efore tr e a tm e n t, a ll p a tie n ts w ere given psychological tests w hich included the M in n eso ta M u ltip h asic P erso n ality Inventory (M M P I,11 the BD I,12 the Sched ule of R ecent E x p erien ce (SR E ),13 an d th e S ta te - T r a it A n x ie ty In v e n to ry (S T A I).14 W hen testin g was com pleted, p a tie n ts w ere sc h e d u le d fo r a d e n ta l e x a m in a tio n . A fter th a t e x a m in a tio n , w ith o u t access to results of psychological testing, faculty d entists from the clinic w ere asked to in d icate th e presence or absen ce of d e p re ssio n , a n x ie ty , recen t stress, an d d enial on a L ikert scale. T h e q u estio n n aire used by the dentists is show n in F igure 1. T h e sensitivity an d specificity estimates of the d entists’ L ikert scale ratings were com puted as follow s. A d en tist’s ratin g of 0 was regarded as a negative finding an d a score of 1 or greater was regarded as a positive fin d in g . T hese were com p are d w ith th e fin d in g s based on psy-
3
moderate
5 severe
moderate
2. Do you characterize this patient as being anxious or tense? Yes or No If yes, rate severity: 1 2 3 mild
4
4
5 severe
3. Do you think this patient has experienced a lot of stressful situations during the past year? Yes or No 4 5 If yes, rate severity: 1 2 3 mild
moderate
severe
4. Do you think this patient exhibits defensiveness and denial (minimizing problems in life such as stress, or interpersonal conflict)? Yes or No If yes, rate severity: 1 2 3 4 5 mild
moderate
severe
Fig 1 ■ Questionnaire using Likert scale given to dentists after examining study subject.
RESEARCH
ch o lo g ic a l test scores. S e n sitiv ity w as c o m p u te d by d iv id in g th e n u m b e r of people rated positive, b o th by d en tists’ r a tin g s a n d p sy c h o lo g ic a l te s tin g , by the total num ber of persons rated positive ac co rd in g to p sy c h o lo g ic al test scores. T h is fra c tio n is m u ltip lie d by 100 to y ield a p erc en ta g e. S p e c ific ity is also expressed as a percentage an d is com puted by dividing the n um ber of people rated neg ativ e b o th by d e n tis ts ’ ra tin g s a n d psych o lo g ical testing, an d by the total n u m b e r of p e o p le r a te d n e g a tiv e by psychological testing. Results D e n tis ts ’ c lin ic a l im p r e s s io n s o f th e p re se n c e o r ab sen c e o f p s y c h o lo g ic a l p ro b lem s w ere co m p ared w ith criteria based on standardized psychological tests th a t served as the g old standard. G old sta n d a rd crite ria w ere based o n cuto ff scores th a t corresp o n d w ith com m only accepted clin ic al th re sh o ld s of distress for the p ertinent psychological variable. T h e exception to this ru le was state and trait anxiety in w hich the gold standard was d efin ed as scores g rea ter th a n the 83rd p ercen tile. T h is co rresp o n d s to a sco re 1 s ta n d a r d d e v ia tio n ab o v e th e mean. T h e g o ld sta n d a rd c rite ria a n d c o r re s p o n d in g base ra te s fo r ea ch of the p s y c h o lo g ic a l v a ria b le s in th is T M D sam ple are as follow s: depression (BDI > 9) = 28%; state a n x ie ty (S T A I > 83 p e rc e n tile ) = 24%; tr a it a n x ie ty (ST A I > 83 percentile) = 38%; recent life stress (SRE > 300) = 53%; denial (M M PI K > 70T) = 7%. T h e m eans, sta n d a rd devi ations, an d ranges for psychom etric scores observed in this T M D sam ple are p re sented in T ab le 1. S ensitivity a n d spe cificity were co m p u ted for each of the psychological variables rated by dentists. T h e results of these analyses are presented in T ab le 2, sh o w in g sen sitivity ranges fro m 88% for state an x iety , to 56% for d e n ia l; a n d s p e c ific ity ra n g e s fro m a low of 19% for state anxiety to a h ig h of 58% for denial. Also, the ratings w ith th e h ig h e s t s e n s itiv ity h a d e x tre m e ly low specificity. C o m p u tin g sensitivity an d specificity in v o lv e s d ic h o to m iz in g th e d e n tis ts ’ ratings in terms of the presence o r absence of th e v a rio u s p s y c h o lo g ic a l fac to rs. D e n tists ’ ra tin g s can also be reg ard ed in a m ore c o n tin u o u s fash io n a n d are co m p ared w ith the p sy c h o m e tric g o ld sta n d ard by c o m p u tin g a P earso n cor r e la tio n c o e ffic ie n t. T h e c o r r e la tio n s
REPORTS
Table 1 ■ Means, standard deviations, and ranges for psychometric scores. Variable
Mean
SD
Range
N
Age Beck depression inventory STAI-state anxiety STAI-trait anxiety SRE-life stress rating MMPI-K Scale (denial)
40.7 8.71 53.74 59.46 479.74 56.50
12.0 8.40 32.74 33.71 437.22 8.36
19-64 0-41 2-100 0-100 0-2511 36-79
107 107 104 104 97 107
Table 2 ■ Sensitivity and specificity estimates for dentists’ ratings of psychological variables (gold standard = psychological test scores). Variable Dentist anxiety rating (trait) Dentist anxiety rating (state) Dentist life stress rating Dentist depression rating Dentist defensive/ denial rating
Sensitivity
n
Specificity
n
Gold standard base rate
80%
40
19%
65
38
88%
25
21%
80
24
84%
50
27%
45
53
74%
39
56%
68
28
53%
36
58%
71
34
betw een d e n tis ts ’ ra tin g s a n d th e c o r re sp o n d in g psy ch o lo g ical test for each p sy c h o lo g ic a l v aria b le are: d ep ressio n (.20), state a n x ie ty (.12), tr a it a n x ie ty (.08), d e f e n s iv e n e s s /d e n ia l (.02), a n d recent life stress (.34). T h e e x te n t of a g re e m e n t b etw e en d en tists’ ratin g s an d p sychological test g o ld s ta n d a rd s w as also e s tim a te d by c o m p u tin g k,15 as su m in g h o m o g en eity of d e n tis ts ’ r a tin g s d is trib u tio n s . T h e resu lts of these analyses are p resen ted in T able 3. It co u ld be a rg u e d th a t th e rela tiv e “cost” of false-positive or false-negative ratings depends on the extent of actual p s y c h o p a th o lo g ic a l c o n d itio n s in a p a r tic u la r p a tie n t. T h a t is, a falsenegative ra tin g w o u ld be m ore serious w hen the actual psy ch o p ath o lo g ic co n d itio n is severe th a n if it w ere m ild . T h e re fo re , a w e ig h te d k a n a ly sis w as com puted th a t assigns a heavier w eight to cases in w hich the discrepancy between the gold standard an d the dentists’ ratings are larger. W eights p ro p o rtio n a l to the distance from the d iagonal of the m atrix of r a te r a g re e m e n ts w ere u s e d .15 T h e results of these analyses are also presented in T a b le 3, sh o w in g th a t th e level of ag reem ent betw een d en tist ratin g s an d psychom etric gold standards are low for the w eighted k analyses. An u n w eig h t ed analysis (not show n) yielded sim ilar results. k
Discussion D entists’ ratin g s as a screening procedure h ad low sp ecificity for a ll of th e p sy chological factors, a n d corresponded to m isclassifying from 44% (depression) to 81% (state anxiety) of the true negatives. R e g a rd in g sen sitiv ity , d e n tis ts ’ ra tin g s of depression, d en ial, an d tra it anxiety w ere re la tiv e ly u n s e n sitiv e a n d c o rre sponded to m isclassifying from 20% (trait a n x ie ty ) to 47% (d e n ia l) o f th e tru e p o sitiv es. D e n tis ts ’ r a tin g s w ere m o st sensitive for state anxiety (88%) an d life stress (84%). H ow ever, these h ig h se n sitivity values were offset by low spec ificity values (19% an d 27%, respectively). A lso, th e re w ere n o la rg e c o rre la tio n s betw een d e n tists ’ ra tin g s a n d th e g o ld standard m easures of depression, anxiety, denial, o r recent life stress. Furtherm ore, an a ly se s in d ic a te d th a t th e level of agreem ent between den tists’ ratings and categorized psychological test gold stan d ard s w ere low . T h e se resu lts su g g est th a t a s c re e n in g p ro c e d u re b a s e d o n d e n tis ts ’ g lo b a l im p r e s s io n s fro m an in itia l e x a m in a tio n do n o t ad e q u ately id e n tify p s y c h o lo g ic a l p ro b le m s in a T M D p o p u latio n . T h e values of sensitivity an d specificity are affected by th e cu to ffs ch o se n fo r d e n tist ra tin g s a n d p sy c h o m etric g o ld s ta n d a rd s . F o r e x a m p le , r a th e r th a n choosing a d en tist ra tin g > 1 as a positive, k
Oakley-Others : PSYCHOLOGICAL PROBLEMS IN PATIENTS W ITH TM DISORDERS ■ 729
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REPORTS
Ta b le 3 ■ Extent of agreem ent betw een d e n tis ts ’ ratings and psychological test gold standards: weighted kanalyses. Weighted Psychological variable Depression Anxiety (state) Anxiety (trait) Recent life stress Defensive denial
Agreement k
SD (K )
(%)
Chance (%)
0.21 0.52 0.54
0.07 0.04 0.54
0.68 0.49 0.53
0.59 0.46 0.50
0 .1 1
0.09
0.57
0.52
0.07
0.07
0.65
0.63
ratings > 3 could have been used as the c u to ff fo r p o s itiv e in d ic a tio n s o f th e p a r tic u la r d iso rd e r. T h is w o u ld have the effect of increasing specificity w hile p ro d u c in g a co rresp o n d in g decrease in sensitivity. U sin g d e n tists’ ratin g s > 0 as the cutoff has the effect of m axim izing sen sitiv ity. In th is study, sensitivity is the m ost im p o rta n t issue. T h e ratings dentists give patients could be regarded as a first step in screening; those individuals w ho are rated positive by d e n tists can be referred for follow u p e v a lu a tio n u sin g stan d ard ized psy chological tests. However, in this study, th at decision w ould have resulted in m any in d iv id u a ls b e in g re fe rre d for te stin g w ho did n o t need it. A related issue is the u n k n o w n sub jective fram e of reference that the dentists w ere u s in g w h en m a k in g ratin g s. T h e w eighted analyses provide no evidence th a t d e n tis ts ’ a g re e m e n t w ith p sy c h o m e tric g o ld s ta n d a r d s im p ro v e s w ith in c re a s in g severity of d e n tists’ ra tin g s o r psychom etric criteria. In a d d itio n , p sy ch o lo g ical p roblem s m ay n o t be obvious or reliably detected by im p re ssio n s from a n in itia l e x a m ination. T h is has im p o rta n t im plications for th e tim in g of q u e s tio n s re g a rd in g p sych o logical status. T herefore, if psy chological status is p u rsued only w hen th e c l in ic ia n th in k s th e re m ay be a problem , m any psychological problem s w ill go u n d etec ted . I t is p o ssib le th a t d en tists co u ld m ore accurately identify psychological problem s in a TM D p ain p o p u la tio n if they placed m ore em phasis on system atically exploring psychological distress in the in itial dental exam ination an d m edical interview , o r if they were train ed to identify psychological p ro b lems. T h e p s y c h o lo g ic a l tests th a t served as the g old standard criteria in this study a re a su b se t of o th e r tests th a t c o u ld also be used as gold standards. Therefore, k
730 ■ JADA, Vol. 118, June 1989
k
conclusions can n o t be generalized beyond th e set o f p s y c h o lo g ic a l tests u sed in this study. Also, the psychological tests used in this study have lim itations shared w ith m a n y p sy c h o lo g ic a l tests. F or exam ple, a p atien t could respond falsely or random ly. These concerns are partially addressed in th e v a lid ity scales of the MMPI. M M PI scores of K > 70T have been su g g e ste d to in d ic a te d e fe n s iv e n e s s / d e n ia l,1618 an d in the case of test-taking, the tendency to fake good (for exam ple, present oneself in a favorable way w hen conditions are n o t favorable).17 T h e use of k as a m easure of denial in th is study m ust be qualified in th at it is a com plex m e asu re of m an y o th e r factors. It has been su g g ested to be an in d ic a tio n of efforts to a p p e a r ad eq u ate, in co n tro l, and effective, as well as to reflect serious lim ita tio n s in p e rs o n a l in s ig h t a n d u n d erstan d in g .18 Conclusions T h e psychological factors studied in this investigation are am ong several of interest in the T M D p o p u la tio n . F u tu re inves tig a tio n s co u ld focus o n o th er psy ch o logical factors such as hypochondriasis, hysteria, or an g er/h o stility . Finally, these r e s u lts do n o t im p ly e n d o rs e m e n t o f p s y c h o lo g ic a l te s tin g w ith a ll T M D patients as the p articu lar variables studied in this investigation have yet to be proved as c o n s is te n tly re la te d to tr e a tm e n t o utcom e. A d d itio n al in v estig atio n s are needed. -----------------------J!SOA\ ----------------------This research was supported by NIDR grant no. DE07618. Dr. Oakley is assistant clinical professor of psychiatry and biohavioral sciences, School of Medicine; Dr. McCreary is clinical professor, School of Medicine, department of biobehavioral sciences; Dr. Flack is assistant professor, School of Public
Health, division of biostatistics; Dr. Clark is professor, School of Dentistry; Dr. Solberg is professor, School of Dentistry; and Dr. Pullinger is associate professor, School of Dentistry, University of California. Address requests for reprints to Dr. Oakley at University of California, Los Angeles, UCLA Dental Research Institute, Center for the Health Sciences, 73-029, Los Angeles, 90024-1762. 1. Follet W, Cummings NA. Psychiatric services and medical utilization in a prepaid health plan setting. Med Care 1967;5:25-35. 2. Goldberg ID, Krantz G, Locke BZ. Effect of a short term outpatient psychiatric therapy benefit on the utilization of medical services in a pre-paid group-practice medical program . Med Care 1970;5:419-28. 3. Jameson J, Shuman LJ, Young WW. The effects of outpatient psychiatric utilization on the costs of providing third party coverage. Philadelphia: Blue Cross of Western Pennsylvania, 1976; research series 18. 4. Olson RE. Behavioral examinations in MPD. In: The president’s council on the exam ination, diagnosis, and management of temporomandibular disorders. Chicago: American Dental Association, 1983; 104-5. 5. Nielson AC, W illiams TA. Depression in ambulatory medical patients: Prevalence by selfreport questionnaire and recognition by non psychiatric physicians. Arch Gen Psychiatry 1982;37:999-1004. 6. Eastwood MK. Screening for psychiatric dis orders. Psychol Med 1971; 197-208. 7. Goldberg DP, Cooper B, Eastwood MR, Kedward HB, Shepard M. A standardized psychiatric interview for use in community surveys. Br J Prev Soc Med 1970;24:18-23. 8. Knights EB, Folstein MF. Unsuspected emo tional and cognitive disturbance in medical patients. Ann Intern Med 1977;87:723-4. 9. Hesbacker PT, Rickels K, Goldberg D. Social factors and neurotic symptoms in family practice. Am J Public Health 1975;65:148-55. 10. Morton RF, Hebei JR. A study guide to epidemiology and biostatistics. Baltimore: University Park Press, 1979. 11. Minnesota Multiphasic Personality Inventory, copyright 1943 [Psychological test]. The Univ of Minn Nat Comput Syst Inc, PO Box 1416, Min neapolis, 55440. 12. Beck AT. The Beck Depression Inventory, copyright 1978. [Psychological test]. Center for cognitive therapy, Room 602, 133 S 36th St, Philadelphia, 19104. 13. Holmes TH, Rahe RH. The social readjust ment rating scale. [Psychological test]. J Psychosom Res 1967;11:213-8. 14. Speilberger LD, Goruch RL, Lushe R, Vagg PR, Jacobs GA, copyright 1968, 1977 by Charles P. Spielberger. [Psychological test]. Consulting Psychologists Press, 577 College Ave, Palo Alto, CA 94306. 15. Fleiss JL. Statistical methods for rates and proportions. 2nd ed. New York: Wiley 8c Sons, Inc, 1981:222-5. Weighted kappa: eq. 13.29. Standard deviation: eq. 13.36. Weights proportional to distance: eq. 13.31. 16. Lachar D. The MMPI: Clinical assessment and automated interpretation. Los Angeles: Western Psychological Services, 1974:3. 17. Graham JR. The MMPI: a practical guide. 2nd ed. New York: Oxford University Press, 1987:25-
8. 18. Dahlstrom WH, Welsh GS, Dahlstrom LE. An MMPI handbook. Volume 1: Clinical inter pretation. Minneapolis: University of Minnesota Press, 1967:166.