Wilson, David A.*; Cronjé, Sonja†; Frick, Kevin‡; Holden, Brien A.§
Uncorrected refractive error, including presbyopia, is the major cause of global visual impairment. Fortunately, it has a relatively simple solution: spectacles. More than 670 million global cases of distance and near uncorrected refractive error1,2 live in developing countries and, as a result, they often rely on external help from visiting professionals and non-government organizations. Some have responded with the use of recycled spectacles. Indeed, common approaches taken by programs targeting the problem of uncorrected refractive error appear to use either ready-made spectacles or recycled spectacles supplied by visiting teams of professionals.3–5 Although recycled spectacles are nominally free, the actual cost of delivering these spectacles to the wearer is substantial and has not been reported in the literature. Getting recycled spectacles from the donor to the end user involves a number of potentially costly processes. Recycled spectacles must be collected from the place where the spectacles were donated by the original owner of the spectacles and brought to a central repository. They must then be culled, with those passing the initial screening then checked on a focimeter (lensometer), cleaned, sorted, labeled, shipped, and stored before they can be used in a refractive error program. These processes entail significant transportation and labor costs. This article tests the hypothesis that recycled spectacles are not a cost saving approach to correcting refractive error in developing countries.
To calculate the cost of delivering recycled spectacles, it is necessary to determine the proportion of any batch that will be useable in a refractive error program and estimate the time and resources spent both on useable and discarded spectacles.
Determining Usable Quantity
Two batches of donated spectacles were examined to determine the useable quantity. Batch 1 was a single box sent to the National Medical Stores, Honiara, Solomon Islands. The box, still as packaged by the donor organization, contained 106 spectacles. Batch 2 was a box sent to the International Centre for Eyecare Education in Australia. The box contained 169 spectacles collected from optometry practices in Sydney and Canberra.
All spectacles were given an initial inspection and were eliminated if they met any of the following criteria:
* progressive lenses;
* lenses with noticeable scratches or flakes;
* lenses with noticeable cylinder power; and
* damaged frames.
Progressive lenses were considered unsuitable because of their need for accurate optical alignment and fitting, especially of the corridor between the distance and near zones, and the relatively small chance of a pair of spectacles meeting both the refractive and alignment requirements of the recipient.
Spectacles that passed the first screening were then checked by an observer (David Wilson) using a Topcon LM-S1, Japan, focus-on-axis (telescopic) focimeter. Spectacles failed the second inspection if they met any of the following optical criteria:
* >0.75 D cylinder power;
* >0.5 D anisometropia; and
* >0.5 Δ of differential vertical prism.
The first two above recommendations are from the Refractive Error Program Committee of the International Agency for the Prevention of Blindness6; and the third is based on the tolerances for vertical prism recommended by the authors. The third recommendation also complies with the tolerance for vertical prism in the new international standard.7 The criteria used to judge useability did not include cosmesis; only power and optical and physical condition were considered.
The cost of delivering both recycled and ready-made spectacles was determined and compared with the cost of delivering ready-made spectacles using a cost minimization approach. Cost minimization is an economic evaluation approach appropriate when the outcomes are the same for the alternative approaches being compared. Although this technique is not often used as a tool for cost comparisons in the health economics field, where the benefits or utility of alternative approaches may differ,8,9 it is valid where the effects of alternative programs are demonstrably similar or where there is a defined minimum outcome.10 Both ready-made spectacles and recycled spectacles aim for the same minimum visual outcome of >6/12 visual acuity. The strategies are also the same, involving the spectacles and the principle of best vision sphere. Furthermore, in addition to similar visual outcome targets and strategy, the outcomes in terms of spectacle utilization have also been found to be similar. Two recent studies in India and China11,12 showed little difference in spectacle utilization between ready-made spectacles and custom-made spectacles. Table 1 shows the costs considered in the calculations below.
As possible, many of the identifiable costs attached to a particular option were included, even where they may have been common to both ready-made spectacles and recycled spectacles. Although an attempt was made to use real costs wherever possible, some assumptions were made in assigning costs to inputs. One common set of costs that were excluded were program costs such as advocacy and research. They were not considered to be directly involved in the delivery of the relevant appliances dispensed by the program.
The following assumptions were made in determining costs:
* An economic costing approach was used rather than a strictly accounting approach. This involved assigning an opportunity cost to volunteer labor. There are two reasons for choosing this approach. First, the economic imperative of valuing opportunity cost, i.e., recognizing that the volunteer labor could have been doing something else, is potentially more productive. Second, programs are not guaranteed of continuing free labor. Therefore, the real cost of a program must include the actual cost of labor to deliver the program as if volunteer labor were not available.
* The wages were determined using published data for Australia.13 The level used was that of a recent optometry graduate, because the labor used for tasks such as checking ready-made spectacles or recycled spectacles is often final-year university students or young volunteer optometrists.
* Tariffs used were the most favored nation non-agriculture tariff of Australia.14
* All costs initially determined in Australian dollars were converted into US Dollars using the exchange rate at 29 May 2009 of $AUD1.00 to $USD0.793.15
Although the purchase price of ready-made spectacles from the manufacturer is low, the real cost of delivery should factor in the labor involved in quality control. It was assumed, based on the experience of the authors, that a full quality check required about 5 min (i.e., 12 pairs of spectacles checked per h) whereas a brief visual inspection would have taken 15 s. It was also deemed that powers between −2.50 and +2.50 D would not require a focimeter check, which is based on a study of 700 ready-made spectacles of powers between −6.00 and +6.00 D performed by one of the authors (DW).
Hourly wages were calculated assuming a 50-working week year, 5-day working week, and 7-h working day. Thus, the hourly wage for the recent graduate was determined to be U.S.$26.85. The prices of ready-made spectacles were obtained as the mean of those listed by International Centre for Eyecare Education's Global Resource Centre16 in U.S. Dollars ($1.88USD landed cost).
Costs of delivering recycled spectacles were calculated in two ways. First by assuming the useable proportions found from analysis of the two batches. A second costing was then performed based on the upper 95% confidence limit for the useable proportion as a means of indicating a more generous upper limit.
Useable Quantity of Recycled Spectacles
In batch 1, nine spectacles of 106 were found to be useable, although all had minor damage of varying degrees. Of the nine, seven were between +0.25 and +1.50 D. There was only one pair of minus powered spectacles (−1.50). Two of the nine that passed inspection were bifocals, which would not be ideally suited to prepresbyopic ametropes, leaving seven useable pairs.
For batch 2, 11 of the 169 were found to be useable; again, all had some minor damage. Of the 11, nine were between +1.00 and +2.50 D, with four pairs of +1.00 D. There were only two pairs of minus powered spectacles (−0.75 and −3.00 D).
The result of the analysis of the two batches of recycled spectacles is shown in Table 2. Overall, only 7% were found to be useable with a 95% confidence interval of 5 to 11%. Batch 1 contained 32 progressives and batch 2 had seven progressives; and no aspherics were found in either batch.
Ready-Made Spectacles (Using Personnel in a Developed Country)
The cost of delivering a pair of ready-made spectacles of powers ≤2.50 D, where only a brief quality check is performed, is U.S.$11.28. If a full focimeter check were performed, it would add a further U.S.$1.95 to the cost of each pair (Table 3). Although some spectacles would be rejected as a result of the quality control process, it is assumed that the original manufacturer would bear the responsibility to replace spectacles that are not of merchantable quality. Merchantable quality here is defined as not meeting international tolerances.
Recycled Spectacles (Using Personnel in Developed Country)
Costs were calculated assuming that 23% pass the first visual inspection and 7% would be useable, having passed the focimeter inspection, i.e., 77% of the recycled spectacles can be eliminated after a cursory check and without need for the focimeter. These should include all progressives, however, it would be expected that in other batches, some lower addition progressives may pass the initial cull, as would most aspherics. The remaining 23% will then undergo a focimeter check. Selecting seven useable pairs of recycled spectacles of a batch of 100 will require ∼2 h of skilled labor. The cost of delivery of a pair of recycled spectacles was found to be U.S.$20.49. If we assumed 11% to be useable, the upper 95% confidence limit, the cost was U.S.$17.86 (Tables 4 and 5).
If an accounting approach were used, and the opportunity cost of volunteer labor disregarded, the cost per pair of recycled spectacles would still be more expensive than ready-made spectacles given the greater transport cost per useable pair. Although labor costs would be 0, the transport cost per useable pair would be significantly higher at $11.14 per pair ($78.00 per 100 spectacles transported divided by seven useable) because 15 pairs would need to be transported to obtain one useable pair.
The results of the analysis of the recycled spectacles and the costing of their delivery raise a number of issues for all involved in the process. First and most importantly are the implications for the end users. The recipients of the recycled spectacles are receiving spectacles of variable and questionable quality and style, which are costing the programs involved time and money. For the same outlay or less, they could be receiving a new, reasonable quality pair of spectacles. They are also likely to receive a more suitable style rather than with the forced choice of recycled spectacles. Also, many potential wearers may be uncomfortable wearing recycled spectacles, given the personal nature of the appliance and the reality that spectacles are not necessarily cleaned regularly, other than a dry wiping of the lenses. Even though the recycled spectacles would be cleaned before being dispensed, this perception may still be a problem in their acceptance.
The unpredictable range of styles and sizes of recycled spectacles presents further problems for the end user. For example, the spectacles with the most appropriate power for a particular end user may be of a style designed for the opposite sex. Alternatively, it may merely be a style or shape unsuited to its intended recipient. This would clearly be socially inappropriate. However, the spectacles may simply be the wrong size for the recipient. All these factors are likely to affect spectacle utilization by the end user.
The use of recycled spectacles has development, economic, and social implications for the country or region involved. The supply of recycled spectacles does not help grow a sustainable industry in countries and communities being serviced.17–21 Ramke et al.17 argue that “No amount of efficiency and effectiveness in the delivery chain can justify the output and outcome of this recycling scheme.” Vincent et al.22 also emphasize the need to build local capacity and the need to rely on an evidence-based approach to addressing the problem of uncorrected refractive error.
Finally, there are significant implications for program managers. Even if it were assumed that those with uncorrected refractive error are happy to accept recycled spectacles, the analysis above shows that there are still enormous inefficiencies associated with screening and cleaning the spectacles, along with the lack of uniformity of shapes, styles, powers, and PDs. Ready-made spectacles, however, do provide some uniformity in style and PD, as well as predictable powers.
The age of recycled spectacles and the fact that they have been worn by the original owner for a substantial period will also introduce other problems such as durability. The older the spectacles the more likely they are to be scratched, affecting both the optics and the impact resistance. This is exacerbated by the means of collection, which typically involves throwing the spectacles into a collection bin. Frames too, particularly those made of plastic materials where plasticizers will have degraded over time, will have deteriorated, and be more prone to breakage.
Programs using recycled spectacles are focused only on attempting to meet the optical aspect of refractive error correction and do not sufficiently consider the appearance of the spectacles and the self-esteem of the wearer. This may result in lower levels of utilization than expected, because people may refuse to wear spectacles which they believe make them look different or unappealing. There may be an underlying assumption by providers that appearance is only of concern in wealthier communities and developed countries. However, poor cosmesis and hence embarrassment has been found to be a significant factor in low compliance within developing regions.23 Concern for appearance should not be considered merely an urban phenomenon. Poor cosmesis proved to be a significant reason for unwillingness to wear spectacles in a study performed by Ramke et al.24 in Timor-Leste, a country which is still affected by the results of recent conflict. It cannot be assumed that dignity and concern for one's appearance is a function of and the right of wealth. In contrast, modern ready-made spectacles replicate the appearance, if not the quality, of more expensive and current fashion frames.
The task of meeting a full range of spectacle lens powers is considerable. Screening and culling of a set of recycled spectacles would most likely leave gaps in the available power range, possibly leading to compromises by the delivery team in the field. This is a particular problem in remote programs where filling the gap by ordering ready-made spectacles or custom-made spectacles is not feasible. Based on the sample batches discussed in this study, the number of donated spectacles required to produce a complete set of powers in 0.50 D steps from −6.00 to +6.00 D in spectacles suited to both sexes is likely to amount to many thousands. The compromises might be a “best-can-do” power or an inappropriate style, either of which may contribute to a lack of compliance.
Most, if not all, recycled spectacles are sourced from developed countries. Many of the spectacles likely to be donated, particularly by elderly spectacle wearers, would be unsuitable for use in a refractive error program. All the progressive spectacles are unsuitable, even where the distance power is spherical and matched, given their fitting requirements. Similarly, aspheric single vision lenses also require precise fitting and so are unsuitable for use.
A further problem occurs when the spectacles are merely packaged and sent to a facility in the developing country without any professional support. The box donated to the National Medical Stores, Honiara, was sent without any support or instructions. It was supposed that the Honiara authority would have a use for the spectacles and the cleaning and sorting of the spectacles was also left to the staff in Honiara. Because most donated spectacles proved to be unusable, this effectively meant that the donor organization had packaged and posted, at some considerable expense, spectacles destined to be discarded. It might be argued that a cash donation would be more worthwhile than the time and resources of donors and service groups involved in collecting and sorting recycled spectacles, or that their time and efforts would be better spent on more development-friendly activities such as teaching.
If supported by retail optical organizations, programs receiving and dispending donated recycled spectacles also face a potential conflict of interest and therefore a possible breach of ethics as soliciting donated spectacles might be seen as an inappropriate way to generate more sales of new spectacles to donors. Furthermore, the visibly charitable work of any optical company adopting this approach may be likely to endear donors and therefore make them more likely to purchase spectacles from an organization, which is seen to be a good corporate citizen, when indeed the spectacles are largely unusable.
Finally, because the cost of providing recycled spectacles is between 1.6 and 1.8 times the cost of supplying ready-made spectacles, use of recycled spectacles is clearly not the method that requires the smallest amount of limited non-government organizations and government resources.
David A. Wilson
International Centre for Eyecare Education
PO Box 6328 University of New South Wales
Sydney, New South Wales 1466
We thank those who have offered advice or have assisted by proofreading the manuscript, including Associate Professor Eric Papas and Gerhard Schlenther.
The authors are all involved with ICEE, which sells ready-made spectacles as a part of its refractive error programs; however, none of the authors receive any direct benefit from their sale.
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recycled spectacles; donated spectacles; uncorrected refractive error; uncorrected presbyopia; second-hand spectacles