De door Reeves/het CDC gepropageerde kriteria voor "CVS" ("chronische vermoeidheid")

zijn volstrekt ontoereikend om (alle) patiënten te "herkennen" en niet-patiënten uit te sluiten.

De sensitiviteit van de drie vragenlijstje is onvoldoende:

slechts 65% van de CVS-patiënten uit een eerdere Jason-studie wordt als zodanig "erkend".

Ook de specificiteit was volstrekt onvoldoende:

met de SF36-vragenlijst wordt 83% van de niet-CVS-patienten als CVS-patient aangemerkt!

Niet zo verwonderlijk, want in een eerder onderzoek van Jason bleek dat

38% van de mensen met een majeure depressie tot CVS-patiënt wordt gebombardeerd.

Ongetwijfeld zal het CDC deze kriteria voor chronische vermoeidheid blijven promoten...

Citaten uit de studie:

1. Sensitivity and Specificity of the CDC Empirical Case Definition

The CDC empirical FS case definition

assesses

three specific areas to

determine whether a person meets

criteria for this illness

including:

1) disability, using the Medical Outcomes Survey Short Form-36 (SF-36) [3],

2) fatigue, using the Multidimensional Fatigue Inventory (MFI) [4], and

3) symptoms, using the CDC Symptom Inventory (SI) [5].

The disability criterion

for the Reeves et al. empirical CFS case definition [2]

would be met

by scoring

below the 25th percentile

on any one of

the following four SF-36 sub-scales [3]:

Physical Functioning (less than or equal to 70),

Role Physical (less than or equal to 50),

Social Functioning (less than or equal to 75), or

Role Emotional (less than or equal to 66.7).

The SI [5] assesses information about

the presence,

frequency, and

intensity of

fatigue related symptoms

during the past one month.

The frequency and severity scores

were multiplied

for each of

the eight critical Fukuda et al. [1] symptoms and

were then summed.

[FT

To meet

the Reeves et al. [2]

symptom criterion,

a person

needed to have

four or more symptoms and

a total score greater or equal to 25 on the SI.

To meet the fatigue criterion,

the Reeves et al. empirical

case definition [2] requires

a score on the MFI [4] of

greater than or equal to 13

on the General Fatigue subscale,

or greater than or equal to 10

on the Reduced Activity sub-scale.

3. Results

When using the cutoff scores proposed by Reeves et al. [2],

using either the General Fatigue or Reduced Activity criteria,

95% of those with CFS were identified, indicating good sensitivity,

but the specificity was only .27,

indicating that

few of those without the illness would have been correctly identified.

The AUC for the SI instrument was also low, and

the sensitivity data (.59) suggests that

this symptom scale has significant problems in identifying true cases of CFS.

Finally,

AUC findings for the SF-36 indicate low AUCs, and

using Reeves et al.'s cutoff scores, that the sensitivity is acceptable at .96;

however, specificity is inadequate at .17.

When using all three criteria for fatigue, symptoms and disability,

the sensitivity was at an unacceptably low level of .65.

The sensitivity and specificity outcomes for the Reeves et al. criteria

suggest that

these recommended scales and cutoff points

would not be considered

a good diagnostic tool or selecting CFS cases from the general population.

4. Discussion

The present study investigated

the sensitivity and specificity of the empirical CFS case definition [2]

with diagnosed individuals with CFS from a community based study

that were compared with non-CFS cases.

Findings of the present study indicated

sensitivity and specificity problems with the CDC empirical CFS case definition.

When comparing the overall Reeves et al. criteria,

only about 65% of true CFS cases were identified.

In other words,

these criteria are not able to identify

an acceptable high percentage of individuals who have this illness.

Sensitivity and specificity of the CDC empirical chronic fatigue syndrome case definition.

Psychology. 2010 Apr;1(1):9-16.doi: 10.4236/psych.2010.11002.

Jason, L A; Evans, M; Brown, A; Brown, M; Porter, N; Hunnell, J; Anderson, V; Lerch A.

Abstract

In an effort to bring

more standardization to

the chronic fatigue syndrome (CFS) Fukuda et al. case definition,

the Centers for Disease Control and Prevention (CDC)

has developed

an empirical case definition

that specifies

criteria and instruments

to diagnose CFS.

The present study

investigated

the sensitivity and

specificity of

this CFS empirical case definition

with diagnosed individuals with CFS

from a community based study

that were

compared to non-CFS cases.

All participants completed questionnaires measuring disability

(Medical Outcome Survey Short-Form-36),

fatigue (the Multidimensional Fatigue Inventory), and

symptoms (CDC Symptom Inventory).

Findings of the present study

indicated

sensitivity and specificity problems

with the CDC empirical CFS case definition.

Keywords

Chronic Fatigue Syndrome, Empirical Case Definition,

Centers for Disease Control and Prevention, Fukuda Criteria

http://www.scirp.org/Journal/Abstract.aspx?paperID=1622&JournalID=148

full-text:

http://www.scirp.org/Journal/PaperDownload.aspx?paperID=1622&fileName=Psych.20100100010_41160698.pdf