Table 2 Data collection tools for PACKS study

Tools for use with patient

Kidney Disease QOL-36™ Quality of life of patients will be measured using the Kidney Disease QOL-36™ Survey (KDQOL) [48], a well validated tool in kidney disease which has demonstrated good test-retest reliability on most dimensions (includes general health, activity limits, ability to accomplish desired tasks, energy level, and social activities). Symptoms and problems will also be assessed (questions 17–28) and include items about how bothered a respondent feels by sore muscles, chest pain, cramps, itchy or dry skin, shortness of breath, faintness/dizziness, lack of appetite, feeling washed out or drained, numbness in the hands or feet and nausea. Anxiety and depression will also be assessed using the KDQOL-36™ and is measured within the mental component of the tool (questions 1–12).

EQ-5D-5L The EQ-5D [49] is the National Institute of Health and Clinical Excellence’s (NICE) preferred method of measuring health effects in economic evaluations and it has shown to be a valid instrument for the measurement of health status in renal patients. The use of the new 5 level version, EQ-5D-5L, is also advocated by NICE. It consists of a descriptive system and a visual analogue scale. The EQ-5D-5L will be self-completed by the patients or the Research Nurse and also completed for the patient by the carer (i.e. by proxy). The inter-rater agreement can then be assessed.

POS-S Renal The POS-S Renal was developed in 2011 and is used as a tool to monitor progress in individual symptoms. It is a brief tool, primarily aimed at patients with advanced disease [50].

6 Item Cognitive Impairment Test (6CIT) The 6 Item Cognitive Impairment Test (6CIT) Kingshill Version 2000® was developed in 1983 [51] and is a useful dementia screening tool in Primary Care. The tool will be used to identify cognitive impairment and changes over time during the course of the study.

9-point Clinical Frailty Scale Frailty will be studied using the 9-point Clinical Frailty Scale [52]. The Clinical Frailty Scale© has performed better than measures of cognition, function or comorbidity in assessing risk for death.

Palliative Performance Scale (PPS) The Palliative Performance Scale [53] uses five observer-rated domains correlated to the Karnofsky Performance Scale (100–0). The PPS is a reliable and valid tool and correlates well with actual survival and median survival. It has been found useful for purposes of identifying and tracking potential care needs of palliative care patients, particularly as these needs change with disease progression.

Decisional Conflict Scale (DCS) This will be used to explore satisfaction with decision making from a patient perspective. The scale measures uncertainty and difficulties in the decision making process [54]. The 16 item version measures four domains: a) uncertainty in choosing options; b) unsupported in decision making; c) feeling informed; d) decision is consistent with values. The instrument demonstrates satisfactory reliability and good construct validity [55]. It has been used extensively in the United Kingdom. It will be used with patients at baseline, 6 and 12 months.

Patient Log Questionnaires have been developed using items from the Annotated Cost Questionnaire [56] and the iMTA Valuation of Informal Care Questionnaire [57]. These will measure healthcare resource utilisation (and associated costs) by patients.

Tools for use with carer

EQ-5D-5L Carer quality of life will be measured using the EQ-5D-5L detailed above. Carers will also use the EQ-5D-5L to assess the patient’s quality of life.

Decisional Conflict Scale (DCS) Carers views on the patient’s Satisfaction with Decision Making will also be explored using the DCS. It will be used with patients and carers at baseline and at 6 months.

Carer questionnaire Care-related costs to carers using questionnaires will be captured whilst patient included in study or study end. Cost measures will include caregiver’s lost income and out-of-pocket expenditures for formal care-giving services.

Renal Clinicians/CNS

Qualitative interviews Individual semi-structured interviews with renal physicians/CNS will focus on the decision making process with patients and carers that precedes referral to conservative kidney management. Experiences of physicians related to counselling a patient who makes the decision not to commence dialysis will be captured (For interview guide based on the Decisional Conflict Scale (DCS) (see Table 3)