Background
Methods for addressing fidelity of intervention receipt | Borelli et al. [10] | Johnson-Kozlow et al. [15] | McArthur et al. [16] | Garbacz et al. [14] | Preyde et al. [17] |
---|---|---|---|---|---|
1. Assessed participants’ understanding of the intervention | 40 | 52 | 0 | 69 | 30 |
2. Included a strategy to improve participants’ understanding | 52 | 79 | 0 | 66 | 61 |
3. Assessed participants’ ability to perform the intervention skills | 50 | 59 | 50 | 65 | 39 |
4. Included a strategy to improve participants’ performance of intervention skills | 53 | 69 | 50 | 66 | 64 |
Denominator for proportions presented | 325–332a
| 29 | 10 | 65 | 28 |
Methods
Search strategies
Applied to Titles/Abstracts | Applied to all fields | ||
---|---|---|---|
Fidelity | Intervention | Receipt | Health |
fidelity | Intervention | Recei* | Health |
Integrity | Treatment | Enact* | Illness |
Intervention quality | Program* | Cognitive skill | Disease |
Intervention delivery | Therapy | Behavio* skill | |
Intervention implement* | Pa* knowledge | ||
Treatment differentiation | Pa* acquisition | ||
Reproducib* | Pa* understand | ||
Replic* | Pa* comprehen* | ||
Process evaluation | Repeat | ||
Rehear* | |||
Behavio* Practi*e |
Paper selection
Inclusion criteria |
• Published since Bellg et al. [9] |
• Fidelity of receipt of a health Intervention is assessed (authors had to address receipt using the BCC framework definition of receipt, or had to explicitly refer to other methods used to assess ‘receipt’ or terms considered synonymous such as ‘dose/intervention received’, ‘responsiveness’, or ‘receptivity’). |
Exclusion criteria |
• Not in English |
• Conference or dissertation abstract |
• Published before 2004 |
• Not a health intervention |
• Not about fidelity: The paper does not report intervention fidelity; the study may include potential measures of receipt, but it is not clearly related to fidelity |
• No data on fidelity: The paper is about intervention fidelity, but it does not aim to present data about fidelity assessment (e.g. protocols, systematic reviews) |
• Another type of fidelity: fidelity of receipt not explicitly assessed, or methods for assessing it are not described, and another type of fidelity is assessed (e.g. design, training, delivery, enactment etc.). |
Data extraction
Analysis and synthesis
Results
Study characteristic |
n (%) |
n (%) | |
---|---|---|---|
Design* | |||
RCT | 16 (29.1) | Quasi-experimental | 3 (5.5) |
Cluster RCT | 12 (38.2) | Case study | 1 (1.8) |
Pilot/feasibility | 15 (27.3) | Controlled | 1 (1.8) |
Pre-post design | 2 (3.6) | Unclear | 5 (9.1) |
Intervention recipients | |||
People with health conditions | 17 (30.9) | Employees/workers | 5 (9.1) |
Family/informal carers | 6 (10.9) | Care home staff and residents | 2 (3.6) |
Children/Adolescents | 9 (16.4) | Ethnic minority women | 1 (1.8) |
Healthcare staff | 9 (16.4) | Smokers (adults and adolescents) | 2 (3.6) |
Restaurant customers | 1 (1.8) | Families | 2 (3.6) |
People in weight management classes | 1 (1.8) | ||
Intervention deliverers | |||
Nurses | 10 (18.2) | Counsellor/psychologist | 2 (3.6) |
Allied Health Care professional | 7 (12.7) | Academics | 2 (3.6) |
Organisations (NHS/research council) | 2 (3.6) | Teachers | 1 (1.8) |
Healthcare staff | 5 (9.1) | Teachers and Peers | 1 (1.8) |
Social worker | 1 (1.8) | Music therapist | 1 (1.8) |
Multi-disciplinary team | 1 (1.8) | Specialist Trainers | 1 (1.8) |
Peers | 2 (3.6) | Health educators | 1 (1.8) |
Exercise trainer/physiologist | 2 (2.6) | Graduate nurses OR social workers | 1 (1.8) |
Intervention programme staff | 1 (1.8) | Health educator + teacher | 1 (1.8) |
Team leaders | 1 (1.8) | Unclear | 12 (21.8) |
Level of delivery | |||
Individual | 25 (45.5) | Group | 19 (35.1) |
Both individual and group | 3 (5.5) | Unclear | 8 (14.5) |
Mode of delivery | |||
Face to face only | 28 (69.1) | Telephone | 1 (1.8) |
Online (Internet) | 2 (3.6) | Telehealth | 1 (1.8) |
Text messaging | 1 (1.8) | Unclear/missing | 5 (9.1) |
Mixture | 7 (12.7) |
Papers citing the BCC framework and addressing fidelity of receipt as per BCC definition
Reference (first author) | Intervention recipients | Brief intervention description | BCC definitions of receipt | Other | Methods used to address receipt | ||||
---|---|---|---|---|---|---|---|---|---|
Understanding | Performance of skill | ||||||||
Assess | Enhance | Assess | Enhance | Multicultural factors | Other assessment of receipt | ||||
1Asenlof [44] | People with Pain | Individually tailored behavioural medicine intervention | √ | Intervention content | Intervention session records collected | ||||
Participants’ individual working sheets collected to examine session content | |||||||||
2Battaglia [65] | People with PTSD | Telehealth tobacco cessation program + PTSD Health Buddy program + motivational interviewing telephone counselling | √ | √ | Satisfaction | Self-report Questionnaire | |||
3 Blaakman [66] | Caregivers of children with asthma | Tailored nurse led Motivational Interviewing intervention | Engagement | Review of audiotapes and of nurses’ field notes | |||||
Satisfaction | |||||||||
Questionnaire to assess satisfaction | |||||||||
4 Black [25] | Adult caregivers | Program to promote caregiver capacity to manage future goals | √ | √ | Behavioural change | Documentation of changes in care plan | |||
Verbal verification of understanding of changes | |||||||||
Self-monitoring of behaviour changes | |||||||||
5 Bruckenthal [47] | Patients with chronic knee pain | Coping skills training for pain | √ | √ | √ | Homework completion | Demonstration and practice of skills reviewed during intervention sessions | ||
6 Carpenter [48] | Adult menopausal women | Deep breathing training and practice supported with CD or DVD | √ | √ | √ | √ | Successful attempts to contact participants | Number of participants not reached | |
Number of participants requiring media player to play intervention materials | |||||||||
Availability of hardware to play intervention materials | |||||||||
Observation of demonstration of breathing behaviours | |||||||||
Acceptability | |||||||||
Assessment of ability to complete practice log | |||||||||
7 Chee [28] | Caregivers of people with dementia | Skill-building intervention | Contacts with participants | Log of contacts | |||||
Log of problem areas addressed | |||||||||
Problem areas addressed in intervention | |||||||||
8 Culloty [75] | Mental health professionals | Cognitive-behavioural therapy supervisor training | √ | √ | Acceptability | Direct observations (video-taped) of sessions delivered rated by evaluator against Process | |||
Evaluation of Training and Supervision (PETS) form | |||||||||
Training Acceptability Rating Scale (TARS) questionnaire | |||||||||
Focus group interviews (1/7 questions on receipt) | |||||||||
9 Delaney [61] | Homecare professionals | Training on late life depression screening and interventions | √ | Self-efficacy (with regards to performance of intervention skills) | Knowledge, self-efficacy, attitude questionnaires in relation to intervention content | ||||
Attitude following workshop | |||||||||
10 Dyas [50] | Adult patients with difficulty sleeping and healthcare professionals | Training practitioners to deliver problem-focused therapy, patients’ needs and preferences, and sleep consultation video | √ | Intervention received | Individual interviews on experiences using intervention, intervention received and understanding | ||||
11 Eaton [51] | Adult breast cancer survivors | Web-based cognitive behavioural stress management (CBSM) intervention | √ | Use of intervention materials | Website monitoring of chapter completion | ||||
Self reported computer skills | |||||||||
12 Ford [29] | African American, Latina, and Arab women | Education on breast and cervical cancer | √ | √ | Individual questionnaire items | ||||
13 Kilanowski [31] | Children | Education on healthy eating and physical activity | √ | √ | Attendance | Attendance log | |||
Knowledge of nutrition/physical activity questionnaire (CATCH) | |||||||||
14 Michie [54] | Adults at increased risk of diabetes | Multi-faceted intervention to increase physical activity | √ | Behaviour change and/or maintenance | Self-report (audiotapes) | ||||
15 Millear [77] | Adult employees | Strengths-based resilience-building programme. | Receptivity to carrying out intervention skills in daily life | Self-report (questionnaire items) | |||||
16 Minnick [67] | Medical practices | The intervention, involved: 1. Joining/forming the team, 2. Assessment, 3. Population focused, care, 4. Process, standardisation,5. Team building, 6. Advanced VIP activities, 7. Ongoing VIP work, 8. Second assessment | √ | Accuracy of recall of intervention content (comparison of participants’ recall with deliverers’ recall) | Self-report of intervention content (reports and interviews) | ||||
17 Pretzer-Aboff [33] | People with Parkinson’s | Based on social cognitive theory. Aim to increase self-efficacy and outcome expectations, improve physical functioning and activity and ultimately mood and quality of life. | √ | √ | Direct observation of participants | ||||
18 Resnick [36] | Residents and nurses in Assisted Living communities | Intervention components: (1) Environment and policy/procedure assessments; (2) Education; (3). Developing function-focused goals; and (4). Mentoring and motivating | √ | √ | Perceived effects of exposure to intervention | Focus groups and meetings | |||
19 Resnick [37] | Residents and direct care workers (DCW) in Assisted Living communities | Intervention components: (1) Environment and policy/procedure assessments; (2) Education; (3) Developing function-focused goals; and (4) Mentoring and motivating | √ | Self-report of knowledge of intervention content (questionnaire) | |||||
20 Resnick [35] | Nursing assistants (NAs) and nursing home residents | Educational programme: sessions addressed the philosophy of restorative care, taught ways to integrate restorative care into daily functional tasks with residents (e.g., bathing, dressing), taught the NAs how to motivate residents to engage in restorative care activities, and defined for the NAs a restorative care interaction and taught them how to document restorative care activities on a daily basis. | √ | √ | Self-report of knowledge of intervention content (questionnaire) | ||||
21 Resnick [34] | Older women post hip fracture | The Exercise Plus Program is a self-efficacy-based intervention to increase exercise. The trainer identifies short- and long-term goals, provides verbal encouragement, and education about exercise | √ | √ | Direct observation of participants by evaluator using checklist | ||||
22 Resnick [56] | Adult stroke patients | Task orientated treadmill based aerobic exercise intervention | √ | √ | √ | √ | Attendance | Attendance log | |
Direct observation of participants with checklist | |||||||||
23 Robb [57] | Adolescents/young adults (AYA) undergoing stem cell transplant | Therapeutic music video intervention that uses song writing and video production to encourage self-reflection and communication skills | √ | √ | √ | √ | Engagement | Active questioning | |
Observation of behavioural indicators of participant engagement | |||||||||
24 Robbins [73] | School girls not meeting national guidelines for physical activity | Motivational interviewing counselling sessions to increase physical activity | √ | Attendance | Attendance logs | ||||
Engagement | |||||||||
Audio recordings of all counselling sessions; content evaluated against checklist | |||||||||
25 Shaw [63] | Adults attending a weight management programme | SMS text messaging intervention to promote sustained weight loss following a structured weight loss programme | Acceptability | Self-report of acceptability on intervention via semi-structured interviews | |||||
26 Smith [58] | Patients with type 2 diabetes | Peer support intervention with suggested themes and small structured components | Attendance | Attendance logs | |||||
27 Stevens [39] | Rehabilitation team | Rehabilitation team-training intervention to help members of the rehabilitation team gain knowledge and use the new team-functioning skills. Involved: (1) general skills training in team process (e.g., team effectiveness and problem solving strategies) (2) informational feedback (e.g., action plans to address team-process problems and a summary of team-functioning characteristics), and (3) telephone and videoconference consultation (e.g., advice on implementation of action plans and facilitation of team-process skills) | √ | √ | Active participation in workshop exercises and discussions | Notes and comments based on observation of sessions | |||
Confirmation of receipt of materials from intervention sites | |||||||||
Receipt of written intervention materials | |||||||||
Self-report in feedback evaluation forms | |||||||||
Feedback on workshop | |||||||||
28 Teri [78] | Direct care and leadership staff | Training program designed to teach direct care staff in assisted living facilities to improve care of residents with dementia. Staff are taught to use the activators, behaviours, and consequences (ABC) approach to reduce affective and behavioural problems in residents with dementia by identifying factors within the environment and staff-resident interactions that can altered. | √ | √ | Checklists and notes | ||||
29 Waxmonsky [64] | Providers at community based clinical practices | Standard REP includes an intervention package consisting of an outline, a treatment manual and implementation guide, a standard training program, and as-needed technical assistance. Enhanced REP added customisation of the treatment manual and ongoing, proactive technical assistance from internal and external facilitators. | √ | Attendance | Attendance logs | ||||
Contacts | |||||||||
Record of intervention contacts (number and length) | |||||||||
30 Weinstein [41] | Women and their live born children | The interventions utilised either brief | √ | √ | Satisfaction | Self-report in a feedback questionnaire | |||
Motivational Interviewing | |||||||||
(MI) or traditional Health Education (HE) to provide oral health education, assist women to adopt behaviours associated with optimal oral health, and to seek professional dental care for themselves and their young children. | |||||||||
Use of standardised protocols/manuals to enhance understanding and performance (no assessment) | |||||||||
31 Yamada [42] | Council members and the health care professionals employed in the NICU | Using knowledge transfer strategies to improve use of pain management strategies in hospitalised infants in neo-natal ICU | Acceptability | Self-report of usefulness of implemented intervention strategies (questionnaire) | |||||
Barriers and facilitators to implementation of intervention strategies (meetings) | |||||||||
32 Yates [43] | Adult CABG patients and spouses participating in Cardiac Rehabilitation (CR) | Patients in both groups participated in the full CR program (comprehensive risk reduction, exercise sessions, and educational classes). Spouses/partners in the PaTH intervention group attended CR with the patient and participated in exercise sessions and educational classes to make the same positive changes in exercise and diet (Therapeutic Lifestyle Change [TLC] Diet recommended by the American Heart Association). Spouses in the usual care group were invited to attend the educational sessions that were part of the CR program. | Attendance | Attendance logs | |||||
33 Zauszniewski [45] | Grandmothers who were raising grandchildren | Personal and social resourcefulness skills training. | √ | √ | Use of skills learnt during intervention | Self-report of use of resourcefulness skills (questionnaire) | |||
Self-report of skills learnt and used (qualitative- daily journals/voice recordings) | |||||||||
34 Arends [68] | Workers aged between 18–63 years, diagnosed with a common mental disorder. | Evidence-based guideline directed at structuring physicians’ treatment to help sick-listed workers with mental health problems to return to work, using strategies such as problem-solving. | Intervention components completed | Self-report of number of assignments completed (questionnaire) | |||||
Intervention content received | Self-report of topics discussed (questionnaire) | ||||||||
35 Bjelland [59] | 11–12 year olds | Intervention aimed at reducing intake of sugarsweetened beverages and sedentary behaviour in adolescent school children. | Exposure | Self-report of awareness of intervention components, receipt of and exposure to intervention materials (questionnaire) | |||||
Satisfaction | |||||||||
Self-report of satisfaction (questionnaire) | |||||||||
Receipt of intervention materials | |||||||||
36 Boschman [60] | Construction workers | Intervention aimed at detecting signs of workrelated health problems, reduced work capacity and/or reduced work functioning. | √ | Recall of intervention-related advice | Self-report (questionnaire) | ||||
Intention to act on intervention advice | |||||||||
37 Branscum [26] | YMCA-sponsored after school programs | Knowledge and theory-based childhood obesity prevention intervention implemented in afterschool programs. The knowledge-based intervention chose program activities to mediate behaviour change solely based on building awareness and knowledge, such as being aware of the recommended number of servings of fruits and vegetables. The theory- based intervention used theory-oriented program activities to mediate behaviour change such as taking small achievable steps for learning and mastering new skills. Both interventions also included aspects of making and reading comic books “Comics for Health.” | Feasibility | Self-report (questionnaire) | |||||
Acceptability | |||||||||
38 Brice [27] | Families with recent live births | Infant and child safety focused intervention targeting fire risks, water temperature, electricity, crib hazards, and firearms, as well as potential injuries associated with stairways, pools, and cars. Intervention strategies included the home safety assessment, one-on-one education and counseling, on-site home modifications, further recommendations, and referrals. | √ | Satisfaction | Self-report (questionnaire) | ||||
39 Broekhuizen [46] | Individuals with familial hypercholesterolemia | Tailored lifestyle intervention aiming to reduce cardiovascular disease (CVD) risk by promoting a healthy lifestyle. Included: improving awareness of CVD risk, motivational interviewing, and computer-tailored lifestyle advice. | Use of (Web) materials | Logins | |||||
Website monitoring of module completion | |||||||||
40 Coffeng [74] | Employees | Group motivational interviewing combined with environmental changes to the physical workplace. | Attendance | Self-report of attendance to intervention sessions and use of intervention components (questionnaire) | |||||
Use of intervention components | |||||||||
41 Cosgrove [49] | Patients with a primary diagnosis of COPD | Pulmonary rehabilitation programme that provides patients with disease-specific information and teaches self-management skills through the practical application of activities. Includes: educational materials and resources for both health professionals and patients). | √ | Acceptability | Self-report of acceptability of intervention (questionnaire) | ||||
Satisfaction | |||||||||
Self-report of satisfaction with educational component (questionnaire) | |||||||||
42 Devine [69] | Female employees | Locally adapted obesity prevention intervention involving goal setting, self-monitoring, modelling, and feedback on behaviour. | Intervention content received | Self-report of experiences with intervention and influencing factors (semi-structured interviews and focus groups) | |||||
43 Fagan [62] | Youth communities | The Communities That Care (CTC) operating system provides a planned and structured framework for diverse community partners to utilise advances in prevention science. Includes:, (a) assessing community readiness to undertake collaborative prevention efforts; (b) forming diverse and representative prevention coalitions); (c) using community-level epidemiologic data to assess prevention needs; (d) choosing evidence-based prevention policies, practices, and programs and (e) implementing new innovations with fidelity. | √ | Responsiveness | Self-report of understanding and participation (questionnaire) | ||||
44 Gitlin [70] | Caregivers for patients with dementia | Occupational therapists assess specific needs, concerns, and challenges of caregivers, the physical and social environment, caregiver management approaches, and dementia patient functionality. Involves environmental simplification, communication, task simplification, engaging patient in activities, and stress reduction, and five key treatment principles: client centered; problem solving; tailoring; action-oriented and cultural relevance. | √ | √ | Adequate number of sessions received and skills learnt | Self-report (questionnaire) | |||
Treatment received with respect | |||||||||
45 Goenka [30] | Adolescent Students (6th and 8th Grade) | Intervention involving multiple education sessions, school posters, and parent postcards focused on imparting behavioral skills and contextual knowledge to decrease children’s susceptibility to taking up tobacco in the future. | √ | √ | Enjoyment and communication skills during intervention delivery | Self-report of enjoyment in teaching, communication skills with participants, ease of use of handbook materials, confidence in using intervention strategies (questionnaire) | |||
Confidence in using intervention materials and principles | Self-report on participants’ enjoyment, ease of use of materials, participation and absorption (questionnaire) | ||||||||
Students’ absorption, engagement, participation, ease of use of program materials | |||||||||
46 Jonkers [52] | Chronically ill elderly patients | Minimal psychological intervention to reduce depression in chronically ill elderly persons involving self-monitoring, exploration of links between cognition, mood and behaviour, and action-planning. | Engagement | Self-report of ability to understand and implement intervention principles (questionnaire) | |||||
Intention to implement intervention | |||||||||
Self-report of adherence to previous intervention commitments (checklist) | |||||||||
Adherence to commitments made | |||||||||
Self-report of intention to implement intervention behaviours in daily life (questionnaire) | |||||||||
Satisfaction | |||||||||
Self-report of satisfaction with intervention (questionnaire) | |||||||||
47 Lee-Kwan [71] | Customers of restaurants serving unhealthy foods in deprived areas | A culturally appropriate health eating health promotion intervention in restaurants serving foods high in calories in low-income urban areas. | √ | √ | Exposure to intervention materials | Self-report of exposure to intervention (survey) examining whether intervention materials were seen and whether this impacted behaviour | |||
Behavioural change following exposure | |||||||||
48 Lisha [76] | Adolescent high school Students | A drug prevention programme, with and without combined motivation interviewing. | Attendance | Attendance records | |||||
49 McCreary [53] | HIV patients | The six-session intervention was delivered to small groups of 10–12 participants by 85 trained volunteer peer leaders working in pairs | Engagement in group sessions | Observations of group sessions and ratings assigned on indicators of engagement (checklist items) | |||||
Self-report on observations (qualitative comments) | |||||||||
50 Nakkash [55] | Currently married women, aged 18–49, reporting symptoms of medically unexplained vaginal discharge and low to moderate common mental disorders | Psychosocial intervention package targeting the reporting of medically unexplained vaginal discharge and common mental disorders (depression and/or anxiety). Involves progressive muscle relaxation/guided imagery exercises and weekly structured support groups. | Satisfaction | Self-report of participants’ involvement and participation in intervention sessions (questionnaire) | |||||
Level of involvement | Self-report of satisfaction with intervention (questionnaire) | ||||||||
51 Naven [84] | Health visitors | Distribution programmes involved the distribution of free fluoride toothpaste and a toothbrush to all children in Scotland at the age of 8 months, and targeted distribution to ‘at risk’ children aged 1–3 years in areas of deprivation | Receipt of information on intervention requirements | Self-report of receipt of information on intervention requirements (item in survey) | |||||
52 Pbert [72] | Adolescent (13-17years) smokers/non-smokers/former smokers | Smoking prevention and cessation intervention tailored to the stage of smoking acquisition of adolescents combined, with peer counselling focusing on the social aspects of smoking and development of the ability to resist social pressures to smoking. | Occurrence of possible intervention steps | Self-report of intervention steps received | |||||
53 Potter [32] | Students | Increase children’s exposure to a variety of fruit and vegetables by distributing free fresh or dried fruit and fresh vegetable snacks to all students during the school day. Teachers and school staff were allowed to eat the snacks to serve as role models. Nutrition education and promotion activities were encouraged but not required. | Reactions to program | Self-report of reactions to program (focus groups with separate groups) | |||||
54 Skara [38] | Adolescent high school Students | Combined cognitive perception information and behavioural skills curriculum in a high school to prevent drug abuse. | Responsiveness to program | Self-report of responsiveness to program (questionnaire) | |||||
55 Teel [40] | Older spouse caregivers of individuals with dementia | Intervention targeting healthy habits, selfesteem, communication, and self-care strategies in older adults. Included practicing healthy habits, building self-esteem, focusing on the positive, avoiding role overload, communicating, and building meaning. Specific self-care strategies were explored in the context of an individual’s experiences, relationships, and condition. | √ | Adequacy of communication methods used in intervention | Self-report on helpfulness of intervention to assess understanding of intervention content (interviews) | ||||
Self-report on adequacy of communication methods used (questionnaire) |
Methods used to assess receipt
Frameworks used
Operationalisations of receipt
Assessments of receipt
Objective assessments
Subjective assessments
Assessments collected on intervention deliverers
Assessments collected on intervention recipients
Validity and reliability of subjective assessments
Sample selection for receipt assessment
Timing of receipt assessments
Discussion
Strengths and limitations of the review
Conclusion
Lessons learnt
|
• Fidelity of receipt (as defined in the BCC framework, i.e. assessments of participants’ understanding and performance of skill and strategies to enhance these) remains poorly assessed in health intervention research |
• Reporting of strategies to enhance receipt, i.e. participants’ understanding and performance of skill, remains particularly low. |
• Other frameworks than the BCC have been used to guide fidelity/process evaluation work, but operationalisations of receipt do not always match the definitions of receipt provided in these frameworks |
• The reporting of methods used to assess receipt requires improvement. Reporting was unclear in a number of papers, requiring readers to read manuscripts attentively several times to identify how receipt was operationalised and providing no information on the validity/reliability of the methods used |
• Quantitative and qualitative methods, or a combination of both, have been used to address fidelity of receipt in health intervention research. |
Recommendations for future work
|
• In the early stages of study design, consider how to address fidelity of receipt both in relation to assessments and strategies to enhance |
• Select one or more fidelity frameworks to guide fidelity work (or use an overarching model) and ensure the methods used to assess receipt are consistent with the definitions of receipt in the chosen framework (s) (provide definitions of receipt) |
• Clearly differentiate between fidelity components and other constructs when writing papers (e.g. receipt and enactment are different constructs, therefore methods used to assess them need to be described separately, as well as results). |
• Address and report on the reliability and validity of the methods used to assess receipt |