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proportion of caregivers accessing the service
demographic and clinical characteristics of caregivers
call characteristics (e.g., patterns of use, source of referral, lengths of calls)
reasons for calling
level of satisfaction with the helpline service
acceptability and impact of the helpline service
psychological distress, caregiver burden, unmet needs
self-efficacy, empowerment, involvement in decision-making
Inclusion and exclusion criteria
Participants: Adult caregivers of adult cancer patients (any cancer type or disease stage). Studies only focusing on cancer patients were excluded.
Interventions: Community-based cancer telephone services focusing on improving caregiver health and well-being; studies including cancer dyads (patient and caregiver together) if caregiver data was reported separately.
Control groups: To fully address the research question, randomized controlled trials, single-arm trials (pre-post trials), and studies reporting on the characteristics of caregivers and their satisfaction with cancer helplines were accepted.
Outcomes: There were no restrictions on the type of outcomes for the efficacy trials but studies should target caregiver needs and well-being.
Search strategy and study selection
Risk of bias assessment
Systematic database search
Summary of included studies
Number of papers
Country of origin
The greatest proportion of studies were conducted in the USA (42%), followed by Australia (31%), UK (16%), Netherlands (4%), Canada (2%), Serbia (2%), Nigeria (2%).
Proportion of caregiver contacts
The overall proportion of caregivers contacting cancer helplines ranged from 14%-67% (call audits - caregivers: 14%-47%; cancer patients: 12%-66%)
The majority of caregivers were: middle-aged (40-60 years), female, Caucasian, well educated, resided in urban areas, the spouse/partner of the cancer patient, lived in the same household with the patient. More than one third came from middle to high socio economic backgrounds, were high income earners, and worked part- or fulltime. The majority were caregivers of patients who were receiving active cancer treatment; the most common cancers enquired about were breast, prostate, colorectal, lung, and melanomas.
Most caregivers were first time users, average call duration was 19 min (range: 12-24min). Caregivers most commonly found out about the helpline through health professionals, CIS staff/events, internet or the media.
One-third of caregivers were found to be distressed or depressed and presented with a mean score of 6 on the Distress Thermometer (range 0-10).
Reasons for calling
The most common reasons for calling were to receive emotional/psychological support, to obtain cancer information, to discuss issues related to treatment, symptom management, prevention, diagnosis, and possible causes.
Investigations with a specific research focus (e.g. qualitative or descriptive studies)
Various studies investigated caregivers’ accessing the helpline to answer a specific research question: caregivers living alone compared to general public; caregiver distress, unmet needs, reasons for calling compared to cancer patients; age and gender differences among caregivers; caregivers use of the internet to obtain cancer information; clinical trials discussion by caregivers; distress thermometer administration to caregivers; prevalence of insomnia in caregivers.
Caregivers reported high levels of satisfaction (83%-96%): expectations were met or exceeded and CIS staff was rated very positively; caregivers reported increased cancer knowledge, enhanced communication with healthcare teams, and improved decision making.
Efficacy of intervention studies in improving caregiver outcomes
Two randomized controlled trials focusing on caregiver burden, unmet needs, self-empowerment, distress and post-traumatic growth. Results showed reductions in levels of distress and unmet needs, and an increase in positive adjustment.
One single-arm analysis focusing on changes in caregivers’ level of distress/impact of distress on daily life, and unmet needs. Results showed significant reductions for all outcome variables.
Summary of efficacy studies
Risk of bias
Random sequence generation
Blinding of personnel, participants
Blinding of outcome assessors
Missing outcome data
Selective outcome reporting
Chambers et al. 2014 
Heckel et al. 2018 
Study design, content, and efficacy of interventions
First author, year, country
Participants and sample size
Outcomes of interest
Heckel 2018 
432 (216 caregivers and 216 patients with cancer
Gender and age: Patient:
mean age 59.8 years (Ctrl group), mean age 58.8 years (IN group)
mean age 56.3 years (Ctrl group), mean age 57.2 years (IN group)
RCT, two arms design
Three telephone outcalls versus
Three telephone reminders to self-initiate contact to helpline if needed
Helpline nurse intervention:
4 month duration, including three outcalls to caregivers (at 5-7 days post randomization, 1 months, 4 months).
Distress screening and referral if required, discussion of 6 topics addressing caregiver unmet needs.
Attention control group:
Same duration and number of outcalls to caregivers as helpline nurse intervention, delivered by research staff, reminders to contact helpline service if needed.
Baseline, 1 and 6 months post-intervention
Zarit Burden Inventory (ZBI)
Centre of epidemiologic Studies – Depression Scale (CES-D)
Supportive Care Needs Survey –Partner & Caregiver (SCNS – P&C)
Supportive Care Needs Survey – Patient (SCNS – Pt)
Health Literacy Questionnaire (HLQ)
Health education and impact Questionnaire (heiQ)
Secondary outcomes: (caregiver and patient)
Evaluation of helpline nurse intervention
Intervention had no effect on caregiver burden, but significantly reduced caregiver unmet needs from baseline to 1 months post-intervention.
No intervention effect on patient outcomes.
Intervention was effective in improving self-empowerment in caregivers at risk of depression (having sufficient information to manager their health).
Caregivers perceived the helpline service as helpful in reducing their worries (74%), thinking positively about their situation (78%), and in thinking things through (82%).
Heckel 2018 
(Secondary analysis of Heckel 2018 )
59 years (31-77 range)
38% <55 years
32% 55-64 years
79% spouse, partner
83% lived with patient
56% post-secondary education
Household size: Median 2 persons (1-8 range)
66% major cities
21% inner regional
12% outer regional
Single arm analysis (secondary analysis of a RCT
Helpline nurse intervention:
Three telephone outcalls
4 month duration, including three outcalls to caregivers (at 5-7 days post- referral, 1 months, and 4 months).
Distress screening and discussion of six topics to address unmet needs
Satisfaction survey at 1 months post-intervention
Distress Thermometer (DT)
Six topics raised for discussion
Caregiver satisfaction with helpline service
Changes in caregiver distress and impact of distress on daily activities
Changes in caregiver unmet needs (topics discussed)
95% stated it was worth their time and effort to take part, 82% stated the program was very relevant to their situation, 96% trusted the information and advice given, 96% stated difficult topics and discussions were handled well, 96% found 13 11 20 nurses well organized, 89% stated that information provided by the nurses was used to assist them in their caregiver role, 91% found referrals and links to community services provided were very relevant to them.
DT cut-off met: (distress score =>4, impact score =>3):
42% outcall 1
41% outcall 2
19% outcall 3
Levels of distress and impact decreased significantly over time.
Topics discussed overall:
82% psychological distress, 45% health literacy, 51% physical health, 44% family support, 28% financial burden, 33% practical difficulties.
Caregivers discussing issues related to psychological distress, health literacy, financial, and practical concerns decreased significantly over time.
Chambers 2014, Australia 
Total sample: N=690 (354 patients with cancer and 336 caregivers)
Colorectal (9%) Prostate (9%)
Lung (8%) Gynecologic (7%)
RCT, two arms design
Helpline Nurse: single-session self-management versus
delivered 5-sessions CBT
Helpline Nurse intervention:
One telephone outcall session involving feedback on DT score and brief instruction in evidence-based strategies to reduce stress + Self-management resource kit.
Five telephone CBT sessions, psychoeducation about the psychological impact of cancer, coping and stress management skills, problem solving, cognitive therapy, enhancing support networks + Self-management resource kit.
Baseline, 3, 6, and 12 months post intervention
Brief Symptom Inventory–18 (BSI-18)
Impact of Events Scale (IES)
The Posttraumatic Growth Inventory (PTGI)
Psychological and cancer specific distress, post-traumatic growth
Psychological distress and cancer-specific distress in caregivers (and patients) decreased over time in both arms.
Post-traumatic growth increased over time for caregivers (and patients) in both arms.