Concept Identification: Literature Review and Concept Elicitation Interviews
No hypoparathyroidism-specific PRO measures were identified in the literature or desktop review. Of the seven reviewed studies, three were case studies [
5‐
7], one was a review article [
8], one was the proceedings of an expert panel [
9], one was a clinical trial [
10], and one was an observational study [
11]. The observational study provided the greatest level of detail regarding symptoms reported by patients with hypoparathyroidism and was based on a survey completed by 374 adults with the condition.
Table
1 provides a summary of the symptoms identified from the review. The most commonly cited hypoparathyroidism symptoms identified across the articles were muscle cramps in the limbs, feet, fingers, stomach, or face. Other symptoms commonly cited were muscle spasms; tingling in the fingers, toes, and lips; weakness; muscle pain or discomfort; numbness or pain in the fingers, toes, and lips; and memory problems. One of the reviewed articles [
11] described the most frequent symptoms (those reported via a symptom checklist by more than 50% of 374 patients with hypoparathyroidism) as fatigue; muscle pain or cramping; paresthesia; brain fog or mental lethargy; tetany; joint or bone pain; inability to focus or concentrate; memory loss or forgetfulness; anxiety or fear or inner unrest; sleep disturbances; pain, heaviness, or weakness in extremities; and feeling sad, down, blue, or depressed.
Table 1
Hypoparathyroidism symptoms reported in reviewed sources
Muscle cramps in the limbs, feet, fingers, stomach, or face | |
Muscle spasms in the limbs, feet, fingers, stomach, or face | |
Paresthesia (tingling) in the fingers, toes, and lips | |
Weakness | |
Muscle pain or discomfort in the limbs, feet, fingers, stomach, or face | |
Numbness of the fingers or limbs | |
Pain of the fingers or limbs | |
Memory problems including “brain fog” or memory loss | |
Depression or feeling depressed | |
Chest pain | |
Respiratory problems, bronchospasm, or laryngospasm | |
Chronic headaches | |
Anxiety | |
Pain with menstrual periods | |
Heaviness in extremities | |
Joint or bone pain | |
Disturbance to bowel movements | |
Fatigue | |
Sleep disturbances | |
Gait impacts (shuffling or frozen)a | |
The literature review results were incorporated into the next phase of the research, the concept elicitation interviews. Specifically, these results were used to create a list of symptom probes for follow-up with the participants upon conclusion of the open-ended concept elicitation portion of the interview.
Participant characteristics are provided in Table
2. The mean age across participants (
n = 6) was 53 years (range 32–71), and the mean number of years with hypoparathyroidism across the participants was 17 (range 7–44). Most were female (
n = 5) and white (
n = 5). All had at least some college education, with half being employed full-time and half being unemployed or retired.
Table 2
Participant characteristics: concept elicitation and cognitive debriefing
Sex, female | 5 (83) | 6 (100) | 11 (92) |
Age in years, mean (range) | 53 (32–71) | 44 (33–69) | 49 (32–71) |
Years with hypoparathyroidism, mean (range) | 17 (7–44) | 15 (2–40) | 16 (2–44) |
Race/ethnicity |
White | 5 (83) | 5 (83) | 10 (83) |
Asian | 1 (17) | – | 1 (8) |
Native American | – | 1 (17) | 1 (8) |
Education |
Some college | 2 (33) | 3 (50) | 5 (42) |
College degree | 2 (33) | 3 (50) | 5 (42) |
Professional/advanced degree | 2 (33) | – | 2 (17) |
Employment |
Full-time | 3 (50) | 4 (67) | 7 (58) |
Part-time | – | 1 (17) | 1 (8) |
Unemployed/retired | 3 (50) | 1 (17) | 4 (33) |
Table
3 provides the spontaneous and probed symptoms reported by two or more participants in the six concept elicitation interviews. The results were generally consistent with those of the literature review. All participants spontaneously reported issues with cognition, and all but one also spontaneously reported the symptoms muscle cramps and tingling or numbness. All but two participants spontaneously reported muscle spasms or twitching. Fatigue was also reported by all participants, either spontaneously (
n = 3) or upon probing (
n = 3).
Table 3
Hypoparathyroidism symptom summary table: concept elicitation interviews
Cognitive issues (brain fog, confused thinking, loss of concentration, short-term memory) | S | S | S | S | S | S | S: 6 |
Muscle cramping | S | | S | S | S | S | S: 5 |
Tingling or numbness | S | | S | S | S | S | S: 5 |
Muscle spasms (twitching) | S | S | S | | S | | S: 4 |
Fatigue (fatigue, tiredness, exhaustion) | S | S | S | P | P | S | S: 4 P: 2 |
Feeling anxious or fearful | S | | P | S | S | P | S: 3 P: 2 |
Joint or bone pain | S | S | P | | P | P | S: 2 P: 3 |
Muscle soreness and muscle pain | P | S | | | S | | S: 2 P: 1 |
Feeling depressed (emotional numbness, tearful, hypersensitive) | | | | P | S | S | S: 2 P: 1 |
Pain, heaviness, or weakness in your arms or legs | | P | P | | P | S | S: 1 P: 3 |
Trouble breathing or feeling like your throat is closing | | | | S | S | | S: 2 |
Headache | | | S | | | S | S: 2 |
Constipation | | S | | | S | | S: 2 |
Dry mouth, feeling thirsty, or dehydration | | | S | | S | | S: 2 |
Ears ringing or loud shushing sound | | | | S | S | | S: 2 |
Item Development
On the basis of the results from the literature review, clinical input, and concept elicitation interviews, an initial item pool was developed. The item pool included 20 items assessing the severity of 10 symptoms (two item options were developed for each symptom). The symptoms assessed were muscle cramps, tingling or numbness, muscle spasms or twitching, muscle pain or soreness, bone or joint pain, feelings of body weakness or heaviness, tiredness or fatigue, slowed or confused thinking, feelings of fear or anxiety, and feeling sad or depressed. Alternate question wording and response options, including verbal rating scales and numerical rating scales (ranging from 0 to 10), were developed for each of the symptom items. In addition, on the basis of the results of the interviews and the clinical input (AK), three areas of impact (nonsymptom items) were identified for further evaluation with patients with hypoparathyroidism: the impact of hypoparathyroidism on sleep, ability to exercise, and work.
Qualitative Evaluation (Cognitive Debriefing Interviews)
Participant characteristics are provided in Table
2. The mean age across participants (
n = 6) was 44 years (range 33–69), and the mean number of years with hypoparathyroidism across the participants was 15 years (range 2–40). All were female (
n = 6), and most were white (
n = 5). All had at least some college education, and most were working either full-time (
n = 4) or part-time (
n = 1).
On the basis of the feedback from the first three cognitive debriefing participants, the draft item pool was revised to include two additional symptom items. Specifically, participants identified that two of the original symptoms needed to be separate symptom concepts. Therefore, “numbness and tingling” became two separate items, and similarly, “bone and joint pain” became two separate items. No modifications were made to the impact items.
Upon completion of the next three cognitive debriefing interviews, three symptom items were omitted from the final Hypoparathyroidism Symptom Diary, and one impact item was added. Specifically, participants reported that muscle pain or soreness, bone pain, and joint pain may be associated with other issues rather than their hypoparathyroidism. In addition, an impact item was included to assess family relationships on the basis of the feedback provided about missing concepts described below.
When asked to identify any missing concepts, only two of the six participants described a missing symptom concept, and four participants described a missing impact concept. Regarding symptoms, one participant stated that an inability to regulate body temperature was a missing symptom, while another participant described slowed speech. Inability to regulate body temperature had not been described in the literature or by any of the previous concept elicitation or cognitive debriefing participants, so this symptom was not included. On the basis of evaluation of the participant responses to the item regarding slowed or confused thinking (brain fog), it appeared that the issue regarding slowed speech was being captured in the existing item, so this was also not added as a new item. Regarding the impact items, one participant mentioned including a question about how hypoparathyroidism psychologically impacts lives given that the condition does not have any visible symptoms and therefore others may not perceive it as a serious condition or provide support when needed. Another participant discussed the impact on quality of life, as well as impacts on mood, such as irritability. Finally, two participants mentioned that the impact on family relationships was missing from the questionnaire. For the impacts mentioned by only one participant, given that the primary focus of the diary is to assess symptoms and include key impacts, the two impacts mentioned by only one participant each were not included; however, as two participants reported family relationships as missing, this item was added to the final measure.
The concepts included in the final Hypoparathyroidism Symptom Diary (Table
4) were deemed relevant, were easy to understand and answer, and were interpreted consistently by the interview participants. Participants did not report difficulty recalling the symptoms and impacts experienced over the past 24 h (the stated recall period).
Table 4
Hypoparathyroidism Symptom Diary final item concepts
Symptoms |
Muscle cramps | VRS (5 levels: none to very severe)a |
Tingling | VRS (5 levels: none to very severe) |
Numbness | VRS (5 levels: none to very severe) |
Muscle spasms | VRS (5 levels: none to very severe) |
Heaviness in arms or legs | VRS (5 levels: none to very severe) |
Physical fatigue | VRS (5 levels: none to very severe) |
Slowed or confused thinking (brain fog) | VRS (5 levels: none to very severe) |
Anxiety | VRS (5 levels: none to very severe) |
Sadness or depression | VRS (5 levels: none to very severe) |
Impacts |
Sleep | VRS (3 levels: not at all to very much) |
Ability to exercise | VRS (3 levels: not at all to very much) |
Ability to work (at school, home, or at a job) | VRS (3 levels: not at all to very much) |
Relationships with family members | VRS (3 levels: not at all to very much) |