Diagnostic uncertainty in pediatric chronic pain: nature, prevalence, and consequences.

INTRODUCTION: Diagnostic uncertainty (DU), which is the perception that a label or explanation for a patient's health problem is missing or inaccurate, has been linked to distress, anxiety, and difficulty coping among adults with pain. This study examined the prevalence of DU among youth with chronic pain and their parents and the relation of parent and youth DU with youth pain, pain-related constructs, and health-related quality of life (HRQoL).
METHODS: Participants included 174 youth with chronic pain (M age = 14.28 years; 73% female) and one of their parents (91% mothers) recruited from a tertiary-level pediatric chronic pain program in Canada. Youth and parent DU was assessed using a brief measure of 3 empirically derived yes/no questions regarding whether the youth and parent had received a clear diagnosis/explanation for their/their child's pain and whether they believed there was something else happening with their/their child's pain that doctors had not yet found. Youth reported on their pain intensity, pain interference, pain catastrophizing, fear of pain, and HRQoL.
RESULTS: Thirty-one percent of youth and 28% of parents experienced DU. Seventy percent of parents and youth were in agreement regarding their experience of DU. Youth DU was linked to higher youth catastrophic thinking about their pain. Parent DU was linked to greater youth pain interference and intensity and lower youth HRQoL.
CONCLUSION: Diagnostic uncertainty is experienced by nearly a third of youth with chronic pain and their parents and is linked to worse youth pain, pain catastrophizing, and HRQoL.

1. Introduction

Pediatric chronic pain affects 11% to 38% of youth,[12] with approximately 3% to 5% reporting significant disability.[7,8] In the absence of underlying organic pathology or positive test results, many youth receive a primary diagnosis of “chronic pain”[4] or “Primary Pain Disorder.”[24] As a consequence, youth and their parents may experience uncertainty regarding the diagnosis, prognosis, and treatment.[15] Diagnostic uncertainty (DU), the perception that a label or explanation for a patient's health problem is missing or inaccurate, is associated with higher levels of anxiety, depression, pain intensity,[27] and disability[5] among adults with chronic primary pain. Research suggests that over 40% of adults with chronic low back pain experience DU.[26] However, the prevalence and impact of DU in the context of pediatric chronic primary pain is relatively unknown.

Nearly 40% of parents of youth with chronic primary pain report not accepting or “buying in” to their child's diagnosis,[18] suggesting that the prevalence of DU among parents of youth with chronic pain may be consistent with adult literature. In a qualitative examination of DU among 20 youth with chronic primary pain and their parents, DU was characterized by a relentless search for the “right” diagnosis, which may limit acceptance of a diagnosis and delay or prevent engagement in treatment.[15] A recent topical review proposed that research should examine the prevalence of DU among youth with chronic pain and their parents, and its influence on treatment and pain outcomes.[23] A brief measure of DU was developed for adults with chronic pain,[23,25,26] but has never been used among youth with chronic pain and their parents.

This study aimed to (1) describe the prevalence and nature of DU among youth with chronic pain and their parents, and (2) compare youth pain (intensity and interference), pain-related constructs (pain catastrophizing and fear of pain), and health-related quality of life (HRQoL) in youth with chronic pain who do vs do not report DU and in parents of youth who do vs do not report DU. We hypothesized that prevalence rates of DU would parallel adult literature and that youth and parent DU would be related to worse youth pain, pain-related constructs, and HRQoL.

2. Methods

The current cross-sectional survey is part of the Pain and Mental Health in Youth study. The current aims are distinct from previously published articles on this study.[14-16,22] The study was approved by the institutional health Research Ethics Board. Participants included 174 youth with chronic pain (M = 14.28 years; 73% female, range = 10–18 years) and one of their parents (91% mothers) recruited from a tertiary-level pediatric chronic pain program in Canada. Youth were enrolled from headache (67%), complex pain (28%), or abdominal pain (5%) clinics. Youth were eligible for the study if they were between 10 and 18 years of age and identified as having chronic pain (ie, pain ≥3 months[13]) without an underlying disease (eg, cancer). Youth with a diagnosis of a severe cognitive disability or developmental disorder were excluded. Parents and youth consented and completed self-report questionnaires using Research Electronic Data Capture (REDCap).[6]

2.1. Measures

2.1.1. Parent and youth diagnostic uncertainty

Diagnostic uncertainty was assessed using a brief measure consisting of 3 empirically derived categorial questions, which were constructed from a study investigating DU among adults with low back pain.[25,26] This is the first study to use this measure since it was adjusted for use with any chronic pain condition.[23] Youth and parents responded yes/no to 3 questions presented in Table 1. Research has demonstrated that individuals with chronic pain often simultaneously report having received a clear diagnosis, while believing that something else is happening with their pain.[27] Thus, question 3 is particularly informative in terms of DU and has been linked to adverse outcomes among adults with chronic pain.[23,26,27] Diagnostic uncertainty was therefore operationalized as youth and parents who responded “yes” to question 3. If youth or parents responded yes to questions 1 or 2, they were asked whether or not they agreed with the diagnosis or explanation provided to them.

Table 1

Brief measure of perceived diagnostic uncertainty.

Questions
Youth
1. I have been given a clear label/diagnosis for my pain
2. I have been given a clear explanation about why I have pain
3. I think there is something else happening with my pain, which the doctors have not found out about yet.
Parent
1. My child has been given a clear label/diagnosis for their pain
2. My child has been given a clear explanation about why they have pain
3. I think there is something else happening with my child's pain, which the doctors have not found out about yet.

2.1.2. Youth pain

Youth reported on their pain characteristics using the valid and reliable Pain Questionnaire.[21] Youth reported their average pain intensity in the past 7 days using a validated 11-point numeric rating scale (0 = “no pain”, 10 = “worst pain possible”).[1,30] Youth completed the Pain Interference Subscale of the Patient-Reported Outcomes Measurement Information System (PROMIS) Pediatric Profile-25.[9,11,17,19,20]

2.1.3. Youth pain-related constructs

The Pain Catastrophizing Scale-Child version[3] was used to assess catastrophic thoughts about child pain. The Fear of Pain Questionnaire, child report, was used to assess pain-related fears and avoidance behaviours.[28]

2.1.4. Youth health-related quality of life

Health-related quality of life was assessed using the Pediatric Quality of Life Short Form (PedsQL-SF).[2]

3. Results

Tables 2 and 3 present sample characteristics and key variable associations. Girls reported significantly higher pain interference than boys (P < 0.05). Older youth reported higher pain interference (r = 0.17, P < 0.05), fear of pain (r = 0.24, P < 0.01), and lower HRQoL (r = −0.29, P < 0.01) than younger youth.

Table 2

Sociodemographic and pain characteristics of the sample.

Sample characteristics	N = 174
Child age (M y, SD)	14.28 (2.22)
Child gender (% female)	73.0
Parent gender (% female)	91.3
Child's ethnicity (%)
White	79.3
Two or more ethnicities	8.0
Other	4.2
Black	1.7
Arab/West Asian	1.7
South Asian	1.7
Aboriginal	1.1
Latin American	1.1
Filipino	0.6
Did not want to answer	0.6
Annual household income (%)
<$10,000-$29,999	5.7
$30,000-$59,999	10.3
$60,000-$89,999	12.1
>$90,000	57.5
Did not want to answer	9.2
No income reported	5.2
Pain locations (%)
Multiple locations reported	43.7
Head	72.4
Other	24.7
Muscles and joints	23.0
Stomach	20.1
Legs	12.6
Chest	10.9
Child pain intensity (M out of 10, SD)	5.53 (1.84)
Child pain duration (M y, SD)	3.20 (3.11)

Table 3

Correlations among variables of interest.

Variable	1	2	3	4	5
(1) Youth pain intensity	1	0.50*	0.39*	0.33*	−0.39*
(2) Youth pain interference		1	0.48*	0.50*	−0.60†
(3) Youth pain catastrophizing			1	0.77*	−0.60*
(4) Youth fear of pain				1	−0.65*
(5) Youth quality of life					1

P < 0.01.

P < 0.05.

Participants' responses to the DU questions are summarized in Table 4. Nearly a third of youth (31%) and parents (28%) believed something else was happening with their/their child's pain, which the doctors had not yet found. Twenty-one percent of youth and 17% of parents who reported that they had received a clear diagnosis also reported thinking something else was happening with their/their child's pain. Seventy percent of parents and youth concurred regarding their DU (ie, both responded yes or no to question 3); 16% of parents and 14% of youth reported being uncertain while their child or parent was certain, respectively.

Table 4

Participant responses to diagnostic uncertainty questions.

	Yes n (%)		No n (%)		Total n
	Youth	Parents	Youth	Parents	Youth	Parents
I/my child have/has been given a clear label/diagnosis for my/their pain	72 (42.6)	79 (46.2)	97 (57.4)	92 (53.8)	169	171
I agree with this label/diagnosis	70 (97.2)	76 (96.2)	2 (2.8)	3 (3.8)	72	79
I/my child have/has been given a clear explanation about why I/they have pain	42 (24.9)	73 (42.9)	127 (75.1)	97 (57.1)	169	170
I agree with this explanation	39 (92.9)	68 (94.4)	3 (7.1)	4 (5.6)	42	72
I think there is something else happening with my/my child's pain, which the doctors have not found out about yet.	51 (30.5)	47 (27.5)	116 (69.5)	124 (72.5)	167	171

Table 5 presents descriptive statistics and results of analyses of covariance. Controlling for youth age and gender, youth who experienced DU reported significantly higher pain catastrophizing than youth who did not experience DU. Youth whose parents experienced DU reported significantly greater pain interference, greater pain intensity, and lower HRQoL than youth whose parents did not experience DU.

Table 5

ANCOVA results controlling for youth age and gender.

Variable	N	Uncertain M (SD)	Certain M (SD)	df	F	P
Parent DU
Youth pain interference	165	57.83 (9.07)	54.06 (8.90)	1,161	4.23	0.04
Youth pain intensity	165	6.09 (1.55)	5.27 (1.86)	1,161	5.81	0.02
Youth catastrophizing	164	21.67 (12.44)	18.01 (12.08)	1,160	2.38	0.13
Youth fear of pain	160	35.91 (22.65)	28.50 (19.13)	1,156	3.48	0.06
Youth health-related quality of life	164	57.86 (19.04)	68.14 (19.10)	1,160	7.44	0.01
Youth DU
Youth pain interference	163	56.04 (9.11)	54.49 (9.16)	1,159	0.88	0.35
Youth pain intensity	163	5.90 (1.68)	5.30 (1.86)	1,159	3.81	0.05
Youth catastrophizing	162	22.60 (12.50)	17.42 (11.70)	1,158	6.06	0.02
Youth fear of pain	159	34.90 (18.87)	28.40 (20.55)	1,155	3.45	0.07
Youth health-related quality of life	162	61.25 (19.56)	67.32 (19.01)	1,158	3.37	0.07

DU, diagnostic uncertainty.

4. Discussion

This is the first quantitative investigation of DU among a large sample of youth with chronic pain and their parents. Nearly a third of youth with chronic pain and their parents experienced DU. Consistent with findings among adults with low back pain,[26] a substantial minority of youth and parents experienced DU despite reporting that they received a clear diagnosis for their pain. Serbic and Pincus postulated that such findings may indicate beliefs that a diagnosis may be correct but does not fully capture the cause of the pain.[26] In the current study, most parents and youth who reported receiving a diagnosis also reported agreeing with that diagnosis. Yet, many families, who are imbedded in a tertiary level chronic pain program for primary pain disorders, continue to believe something undiagnosed is causing the pain. This finding alludes to the perception that the diagnosis provided did not fully explain the youth's pain and what was lacking was the core etiology. This has important implications for clinical encounters when a chronic pain diagnosis is provided, suggesting that the diagnosis itself is not sufficient to allay fears and beliefs that something unknown is causing the pain. Qualitative research with youth with chronic pain and their parents has revealed that many parents and youth express needing further explanation for their pain.[10,15] Indeed, a chronic pain diagnosis is often perceived as a diagnosis of exclusion and to not reflect a true understanding of the cause of the pain.[15] Further research is needed to understand how clinicians could tailor their explanation of a chronic pain diagnosis in a way that would reduce DU.

This study is the first to investigate the relation of youth and parent DU with youths' pain, pain-related constructs, and HRQoL. Although youth DU was linked to higher youth catastrophic thinking about their pain, it was parent DU that was linked to greater youth pain interference and intensity and lower HRQoL. In line with the interpersonal fear avoidance model of pain, uncertainty may fuel parental distress and protective responses around child pain, which may facilitate youth avoidance behaviours and influence youth pain interference.[16,29] Further longitudinal research is needed to understand how DU unfolds over time, its temporal relations with outcomes, and what factors during diagnosis and treatment influence DU. Moreover, the direction of the association between youth pain and parent DU remains unknown—that is, whether having a child with worse pain exacerbates parent DU or vice versa.

A limitation of the current study is the dichotomous nature of the DU questions, which may not capture the varying intensity and nuances of DU.[15] Diagnostic uncertainty may fluctuate over time depending on where youth are in their pain and treatment journey, which was not assessed in the current study. Furthermore, the current data are based on self-report; thus, the information provided to families regarding diagnosis is unknown. Future research should examine how DU differs based on chronic pain diagnosis and explanation (eg, etiological vs primary pain). Nevertheless, our findings demonstrate that DU is a common experience among youth with chronic pain and their parents and is linked to worse pain, pain-related constructs, and HRQoL.

Disclosures

The authors have no conflicts of interest to declare.