For this study, different patient reported outcome measures will be collected at baseline, immediately after the intervention or control period (i.e. at 3 months follow-up) and at 6 months follow-up. Completion of the outcome measures is expected to take on average 30 min.
Primary outcome measure
The primary outcome measure of this study is the swallowing quality of life questionnaire (SWAL-QOL). The SWAL-QOL is a 47-item patient-reported outcome measure that consists of ten different quality of life domains namely Food selection (two items), Eating duration (two items), Eating desire (three items), Fear (four items), Burden (two items), Mental health (five items), Social functioning (five items), Communication (two items), Sleep (two items) and Fatigue (three items). Furthermore, a symptom scale (14 items) is included. Based on the 30-items of the first seven mentioned quality of life domains a total SWAL-QOL score can be calculated. All SWAL-QOL scales range from 0 to 100, a higher score indicates more impairment. Finally, three separate questions on nutrition intake (normal, soft, pureed, mostly tube feeding, only liquids, tube feeding solely), liquids intake (all liquids, thick liquids, very thick liquids, thickened liquids, no liquids), and general health (poor, moderate, good, very good, excellent) are included. The SWAL-QOL has been translated into Dutch and validated for patients with head and neck cancer [
33] and laryngeal cancer [
8].
Secondary outcome measures
Secondary outcome measures of this study are the speech handicap index (SHI), the shoulder disability questionnaire (SDQ), the European Organization for Research and Treatment of Cancer generic and head and neck cancer specific quality of life measures (EORTC QLQ-C30 and EORTC QLQ-H&N35) and the Patient Activation Measure (PAM). In addition, the EuroQol-5 dimensions (EQ-5D) and patient-reported outcome measures on healthcare usage and productivity losses will be assessed to enable a cost-utility analysis.
The SHI is a 30-item patient reported outcome measure on speech problems in daily life. Response categories range on a five point scale (never, almost never, sometimes, almost always, always). In addition, the questionnaire includes an overall speech quality item, with four response categories (good, reasonable, poor, severe). A total SHI score can be calculated by summing all items (score ranges from 0 to 120), with higher scores indicating higher levels of speech-related problems. The SHI had been translated into Dutch and validated for use among head and neck cancer patients [
34] and laryngeal cancer patients [
8].
The SDQ is a validated pain related disability outcome measure including 16 items describing common conditions that may induce symptoms in patients with disorders of the shoulder [
35]. All items refer to the preceding 24 h. Options are “yes”, “no” and “not applicable”. The “not applicable” category should be used when the condition referred to has not occurred during the preceding 24 h. A final score will be calculated by dividing the number of “yes” scored items by the total number of items applicable and multiplying this score by 100. The final score ranges from 0 (no disability) to 100 (all applicable items scored “yes”), in which a higher score indicates greater impairment.
The EORTC QLQ-C30 is a cancer-specific quality of life measure developed for repeated assessments within clinical trials. It is developed in a cross-cultural setting and is a valid and reliable instrument for quality of life assessments in various cancer populations, including head and neck cancer patients [
36]. It contains five functional scales (physical, cognitive, emotional, social, role), a global quality of life scale, three symptom scales (pain, fatigue and nausea/vomiting) and six single items (dyspnoea, insomnia, loss of appetite, constipation, diarrhea and financial difficulties). All scales and single items can be converted to a score from 0 to 100. A higher score on the functioning scales or the global quality of life scale represents a better quality of life, whereas a higher score on the symptoms scales or the single items indicate higher level of symptoms.
The EORTC QLQ-H&N35 is a cancer-specific module developed for quality of life assessments in head and neck cancer patients [
37] in conjunction with the EORTC QLQ-C30. It contains seven symptom scales (pain, swallowing, senses, speech, social eating, social contact and sexuality), six symptom items (teeth, trismus, dry mouth, sticky saliva, cough and feeling ill) and five additional items concerning the use of painkillers, nutritional supplements and feeding tube and weight loss or gain. All scales and single items range in score from 0 to 100, higher scores indicate a higher level of symptoms.
The PAM is a 13-item patient reported outcome measure on self-reported knowledge, skills and confidence for self-management of one’s health or chronic condition [
38]. Patients are asked to report their level of agreement with various statements on a four point scale (e.g. strongly disagree, disagree, agree, strongly agree) or to indicate that the item was not applicable. A total score can be calculated by calculating a mean score of all the applicable items (items which were answered on the four point scale), which is transformed to a standardized activation score ranging from 0 to 100.
The EQ-5D consists of five items measuring problems on five dimensions of quality of life (mobility, self-care, usual activities, pain/discomfort and anxiety/depression). Patients can answer they have no problems, some problems or extreme problems [
39]. The resulting profile of answers (one of 243 possibilities) can be transformed to a utility given by the general public: the EQ-5D index using the Dutch index tariff [
40]. Furthermore, a visual analogue scale is included, which represents the patient’s judgment of his own health state on a scale from 0 (worst health state) to 100 (best health state).
Direct medical (healthcare and medication use), direct non-medical (travelling costs and help received from family or friends) and indirect non-medical costs (productivity losses) in the previous 3 months will be measured using an adapted version of the medical consumption questionnaire (iMCQ) [
41] and productivity cost questionnaire (iPCQ) [
42] of the Institute for Medical Technology Assessment of the Erasmus University Rotterdam, the Netherlands, as recommended in the Dutch Health Care Insurance Board (CVZ) guideline [
43].
Sociodemographic and medical data
Sociodemographic characteristics (age, gender, education level and living situation) will be assessed at baseline using a study-specific questionnaire. Clinical characteristics including information on cancer stage (TNM classification) and cancer treatment, time since TL and co-morbidity will be collected from the hospital information system using a study-specific case report form. Co-morbidity will be measured using the Adult Comorbidity Evaluation 27 (ACE-27), in which patients can be classified into one of four grades of comorbidity (none, mild, moderate or severe) [
44]. Besides, a case report form on health care use in the hospital during the study period, including visits to medical specialists, day treatment (e.g. chemotherapy) and hospital admission, will be completed using the hospital information system.