Scottish household survey 2018: methodology and fieldwork outcomes

4 Physical Fieldwork and Physical Survey Form

Summary

• There were three different types of Physical Survey: full surveys, dwelling descriptions, and abbreviated dwelling descriptions.
• All surveyor appointments made by interviewers were allocated for a full physical survey.
• Vacant dwellings and dwellings where an interviewer had not made contact with a householder were allocated to surveyors for a dwelling description.
• For addresses where a respondent had refused to undertake a social interview, surveyors were asked to undertake an abbreviated dwelling description. This type of survey only collected information on the age of the dwelling and the type of dwelling. If this information could not be collected from a public road, they were instructed not to complete any information at all and return a "non-survey".
• The SHS physical survey is a dwelling-based survey of the home and surrounding area and uses a 14 page paper form formatted for use with digital pens.

4.1 Physical survey team

The physical survey team comprised of 62 surveyors and 4 Regional Managers. The Regional Managers also acted as surveyors.

Overall, 38 of the surveyors and all surveyors and Regional Managers had worked on the SHCS under the previous contract, and many had been with the team since the 2002 survey. A one-day refresher briefing with the returning surveyors was undertaken in February 2018. This focused on a number of areas including the devleopment of the SAP methodology, the physical survey's use in policy development and workshop's on maintaining the conversion rate.

In early 2018, 24 surveyors were recruited to the physical survey team. Surveyors were required to be fully professionally qualified. They were recruited from a variety of different dwelling-related professions: chartered surveyors, architects, civil and structural engineers, environmental health officers and building control officers.

New recruits were required to attend a five-day residential training course, which incorporated fieldwork practise, so that all were fully proficient with the methodology used in the SHCS. The training was led by representatives by Ipsos MORI with the Scottish Government providing support and input.

The role of the Regional Manager was to ensure the quality of the surveyor data. This included: the completion of the physical inspections; the use of the surveyor appointment system; return of all work and expenses; the validation of the physical survey forms; and that the contractual obligations of the surveyors were being met. They oversaw the work of each of their surveyors, provided technical advice, attended surveyor briefings, and ensured that surveyors maintained quality and timeliness of output throughout the period of the survey. Regional Managers accompanied all new surveyors on at least two inspections.

4.2 Types of physical survey

There were three different types of Physical Survey:

• full surveys,
• dwelling descriptions, and
• abbreviated dwelling descriptions.

The type of survey required by the surveyors was determined by the outcome to the social interview (see Figure 4.1).

All surveyor appointments made by interviewers were allocated for a full physical survey. Only a completed social survey interview with a full physical survey constituted a paired case.

A full physical survey is a visual inspection of both the inside and outside of a property. The surveyor is required to complete all parts of the physical survey form. Surveyors were required to take four photographs to accompany each full physical survey. The photographs are of the front and the back of the property and two of the surrounding area. The photographs were used in the data validation process (see Chapter 5).

In a small percentage of cases, the appointment made for the surveyor visit was broken by a respondent. In these instances, surveyors were required to make a further 3 visits, with at least one visit during a weekend and one in the evening, in order to try to obtain a full survey. After 4 unsuccessful attempts to obtain a full survey, surveyors were required to complete a short dwelling description survey. This was a short physical survey that provides a summary of the property only.

Vacant dwellings and dwellings where an interviewer had not made contact with a householder were allocated to surveyors for a dwelling description. Surveyors were required to take one photograph of the property for a dwelling description and only required to make 1 visit to these addresses. On occasions, however, surveyors would make contact with a householder at these addresses. In these instances, they were asked to attempt to gain agreement for a full physical survey and pass contact information on to the fieldwork department for a social survey to be organised. An interviewer would then return and undertake the social survey, thereby completing a paired case.

Addresses out of scope of the survey, such as second homes and holiday homes, were also allocated for a dwelling description. This information is used to help derive the calibration totals which are based on the findings from the survey such as household type and age. For these addresses, surveyors were not required to attempt to try to obtain a full physical survey.

For addresses where a respondent had refused to undertake a social interview, surveyors were asked to undertake an abbreviated dwelling description. This type of survey only collected information on the age of the dwelling and the type of dwelling. If this information could not be collected from a public road, they were instructed not to complete any information at all and return a "non-survey".

4.3 Physical survey administration

The administration of the physical survey was as follows:

• At the end of the social interview, interviewers attempted to arrange a firm appointment for the surveyor inspection. Appointments were generally made for between 7 and 14 days after the interview date. Interviewers were asked to make appointments in batches, as far as possible, at intervals of one hour plus travel time between addresses. Interviewers left an appointment card with respondents that gave the appointment time and the telephone number of CA Design Services in case they wished to reschedule the appointment.
• When a respondent was unable to commit to a firm appointment time, interviewers were instructed to put in a dummy appointment time, collect the respondent's contact details and indicate that this was not a firm appointment. CA Design Services would then attempt to arrange a surveyor appointment.
• Following download of the CAPI data, details of the appointments were automatically transferred to CA Design Services secure web-based surveyor appointment system. Information sent included the date and time of the appointment, contact details, whether it was a firm appointment, and any other information that the interviewer deemed helpful to the surveyor (such as directions to the property).
• Details of addresses that did not result in a social interview were communicated to the CA Design Services website for allocation for an appropriate type of survey.
• CA Design Services staff then allocated appointments to surveyors. In advance of each of the fieldwork periods, surveyors were required to supply details of their general availability through CA Design Services' web-based surveyor appointment system to help with the allocation.
• In cases where the initial appointment was not met, surveyors were required to make a further three repeat visits.
• Completed surveys were uploaded onto the SHS physical survey validation system, checked by the surveyor, and then sent to their Regional Manager for sign-off (see Chapter 5).

Staff at CA Design Services' Edinburgh office managed the day-to-day fieldwork process for the physical survey. Helpdesk staff managed communication between respondents and surveyors, booking or re-arranging appointments as necessary. Respondents, social survey interviewers and surveyors were able to contact CA Design Services using a dedicated telephone helpline and an SHS survey email address.

The web-based surveyor appointment system was central to organising and monitoring the progress of the physical survey fieldwork. The website was used by surveyors, Regional Managers, CA Design Services staff and Ipsos MORI. All website users had their own password and were given access to different parts of the site, depending on their requirements.

Surveyors used the survey website to check the appointments that had been made for them, record outcomes of each appointment, record mileage, and to calculate payments due. The progress of individual cases could be viewed on the website by entering the unique case identification number. Additionally, the website system provided information on the progress of the fieldwork overall. Most appointments resulted in a full survey at the first surveyor visit.

4.4 Surveyor variability

In order to minimise the effect of variability between surveyors in completing the physical survey form, and to minimise the bias that this may have on estimates at local authority level, the physical survey fieldwork was subject to a set of allocation rules. These were developed by Communities Scotland around 2001 and comprised the following rules relating to full surveys:

• Each surveyor must work in at least 2 local authorities in each year of fieldwork and at least 3 LAs over the three-year fieldwork period.
• No surveyor should complete more than 25 per cent of the surveys issued in a local authority per year, with the exception of the local authorities Highland, Na h-Eileanan Siar, Orkney and Shetland. Here the level was set at 33 per cent.
• Each surveyor's allocation should contain a mixture of dwelling types approximate to the profile of the area they are working in, over each year of fieldwork.
• Each surveyor's allocation should contain a balance of urban/rural properties approximate to the profile of the area they are working in, over each year of the fieldwork.
• Each surveyor should conduct no more than a maximum number of surveys over each year of fieldwork. This maximum was set as 1.5 times the average number of full surveys issued each year.

4.4.1 Compliance with surveyor allocation rules

Most of the surveyor allocation rules relating to the physical survey fieldwork during 2018 were met.

Rule 1: Each surveyor must work in at least two local authorities in each year of fieldwork and in at least 3 local authorities over the three-year fieldwork period. There were no breaches of this rule.

Rule 2: No surveyor should do more than 25 per cent of the (full) surveys issued in any local authority in any one year, with the exception of the Highlands and the three island local authorities, where no one surveyor should exceed 33 per cent of all (full) surveys. There were no breaches of this rule.

Rules 3 and 4: Each surveyor's allocation should contain a mixture of dwelling types and a balance of urban/rural properties that approximate the profile of the area in which they are working in over each year of fieldwork. Table 4.1 shows the proportion of full surveys conducted by surveyor and property type. It confirms that each surveyor undertook surveys in a mixture
of different dwelling types.

Rule 5: Each surveyor should conduct no more than a maximum number of 1.5 times the average number of full surveys issued to each surveyor each year. For 2018, the maximum was set at 75. There were two breaches of this rule with two surveyors exceeding this number by just a few surveys. One surveyor completed 82 full surveys and one completed 78.

Table 4.1: Full physical surveys by surveyor and dwelling type

Row percentages

Surveyor	Terraced/corner house	Detached	Semi-detached	Tenement flat	Other	Total
1	32%	32%	23%	9%	5%	100%
2	13%	45%	30%	9%	4%	100%
3	28%	28%	12%	20%	12%	100%
4	13%	30%	27%	27%	3%	100%
5	46%	36%	18%	0%	0%	100%
6	43%	43%	14%	0%	0%	100%
7	15%	33%	41%	7%	4%	100%
8	16%	28%	28%	16%	12%	100%
9	15%	35%	21%	17%	12%	100%
10	17%	29%	21%	21%	12%	100%
11	24%	9%	11%	44%	13%	100%
12	13%	25%	26%	28%	8%	100%
13	36%	25%	8%	14%	17%	100%
14	16%	47%	26%	5%	5%	100%
15	33%	21%	18%	12%	15%	100%
16	6%	17%	39%	22%	17%	100%
17	26%	23%	21%	15%	15%	100%
18	23%	30%	24%	14%	9%	100%
19	17%	31%	24%	17%	10%	100%
20	31%	7%	21%	14%	28%	100%
21	19%	16%	13%	38%	16%	100%
22	8%	14%	32%	35%	11%	100%
23	16%	39%	25%	16%	5%	100%
24	20%	25%	14%	35%	6%	100%
25	20%	31%	21%	18%	10%	100%
26	33%	22%	11%	22%	11%	100%
27	19%	7%	21%	41%	12%	100%
28	22%	11%	16%	35%	16%	100%
29	16%	22%	27%	18%	18%	100%
30	7%	19%	21%	36%	17%	100%
31	22%	25%	30%	11%	11%	100%
32	27%	15%	21%	18%	21%	100%
33	40%	10%	15%	25%	10%	100%
34	17%	23%	13%	34%	13%	100%
35	19%	31%	23%	14%	14%	100%
36	15%	44%	29%	2%	10%	100%
37	33%	25%	14%	18%	11%	100%
38	27%	22%	29%	16%	7%	100%
39	10%	26%	32%	29%	3%	100%
40	19%	29%	39%	7%	7%	100%
41	40%	19%	21%	12%	9%	100%
42	26%	36%	13%	16%	9%	100%
43	20%	30%	18%	18%	14%	100%
44	21%	26%	33%	8%	13%	100%
45	24%	24%	26%	16%	11%	100%
46	12%	36%	32%	4%	16%	100%
47	10%	54%	24%	8%	4%	100%
48	34%	30%	17%	9%	11%	100%
49	35%	25%	20%	10%	10%	100%
50	14%	19%	29%	15%	23%	100%
51	23%	24%	14%	21%	18%	100%
52	26%	33%	18%	8%	14%	100%
53	19%	28%	23%	15%	15%	100%
54	17%	21%	28%	17%	17%	100%
55	9%	28%	21%	23%	19%	100%
56	17%	67%	8%	8%	0%	100%
57	28%	32%	20%	12%	8%	100%
58	21%	31%	28%	6%	15%	100%
59	18%	16%	32%	10%	24%	100%
60	21%	30%	30%	15%	4%	100%
61	26%	16%	22%	18%	18%	100%
62	30%	37%	17%	10%	7%	100%
63	25%	40%	18%	14%	4%	100%
64	15%	27%	35%	9%	15%	100%
65	37%	18%	11%	16%	18%	100%
66	22%	16%	10%	35%	17%	100%
All	21%	27%	22%	17%	12%	100%

4.5 Physical survey form

The SHS physical survey is a dwelling-based survey of the home and surrounding area and uses a 14 page paper form formatted for use with digital pens. There were three changes to the form used in 2017. A question on presence of smart meters was added, while question D10 on parking provision was removed. The questions relating to taking meter readings for electricity and gas were also removed.

The physical survey form can be found in the publications section of the current SHCS website^[14]. The survey form included sections relating to:

• type and age of the dwelling;
• types of defects;
• types of amenities;
• heating systems and insulation;
• dwelling measurements;
• external construction and materials used;
• external repairs required; and
• Statutory Action and Tolerable Standards.